Web Book of Regional Science
Regional Research Institute
2020
Computable General Equilibrium Modeling for Regional Analysis
Eliécer E. Vargas
Dean F. Schreiner
Gelson Tembo
David W. Marcouiller
Follow this and additional works at: https://researchrepository.wvu.edu/rri-web-book
Recommended Citation
Vargas, E.E, Schreiner D.F., Tembo G., & Marcouiller, D.W. (1999). Computable General Equilibrium
Modeling for Regional Analysis. Reprint. Edited by Scott Loveridge and Randall Jackson. WVU Research
Repository, 2020.
This Book is brought to you for free and open access by the Regional Research Institute at The Research
Repository @ WVU. It has been accepted for inclusion in Web Book of Regional Science by an authorized
administrator of The Research Repository @ WVU. For more information, please contact
ian.harmon@mail.wvu.edu.
The Web Book of Regional Science
Sponsored by
Computable General Equilibrium
Modeling for Regional Analysis
By
Eliécer E. Vargas
Dean F. Schreiner
Gelson Tembo
David W. Marcouiller
Published: 1999
Updated: November, 2020
Editors: Scott Loveridge
Randall Jackson
Professor, Extension Specialist Director, Regional Research Institute
Michigan State University
West Virginia University
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The Web Book of Regional Science is offered as a service to the regional research community in an effort
to make a wide range of reference and instructional materials freely available online. Roughly three dozen
books and monographs have been published as Web Books of Regional Science. These texts covering diverse
subjects such as regional networks, land use, migration, and regional specialization, include descriptions
of many of the basic concepts, analytical tools, and policy issues important to regional science. The Web
Book was launched in 1999 by Scott Loveridge, who was then the director of the Regional Research Institute
at West Virginia University. The director of the Institute, currently Randall Jackson, serves as the Series editor.
When citing this book, please include the following:
Vargas, E.E., Schreiner D.F., Tembo G., & Marcouiller, D.W. (1999). Computable General Equilibrium
Modeling for Regional Analysis. Reprint. Edited by Scott Loveridge and Randall Jackson. WVU Research
Repository, 2020.
<This page blank>
4
Contents
1 Introduction
1.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1.2 General equilibrium economic models . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Overview of CGE Analysis
2.1 CGE analysis at national and regional levels . . .
2.2 Data and data organization . . . . . . . . . . . .
2.2.1 Social accounting matrices . . . . . . . . .
What is a SAM? . . . . . . . . . . . . . .
How are SAM’s useful for policy analysis?
How is a regional/state SAM constructed?
2.2.2 Using IMPLAN to construct a SAM . . .
The aggregate SAM for Oklahoma . . . .
2.3 Determining parameter values . . . . . . . . . . .
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3 A Competitive Regional CGE Model
3.1 Production system . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1.1 Composite value-added and intermediate inputs . . . . . .
3.1.2 Substitution among primary factors of production . . . .
Primary inputs and their demands . . . . . . . . . . . . .
Intermediate inputs and their demands . . . . . . . . . .
3.1.3 Substitution among types of factor inputs . . . . . . . . .
3.1.4 Net output price . . . . . . . . . . . . . . . . . . . . . . .
3.2 Commodity markets . . . . . . . . . . . . . . . . . . . . . . . . .
3.2.1 Market outlets for regional output . . . . . . . . . . . . .
3.2.2 Commodity consumption by households . . . . . . . . . .
Household commodity demand systems . . . . . . . . . .
Commodity substitution of imports for domestic product
3.2.3 Institutional markets . . . . . . . . . . . . . . . . . . . . .
3.2.4 Commodity prices . . . . . . . . . . . . . . . . . . . . . .
Composite purchase price . . . . . . . . . . . . . . . . . .
Composite output price . . . . . . . . . . . . . . . . . . .
3.2.5 Commodity market equilibrium . . . . . . . . . . . . . . .
3.3 Factor markets and factor incomes . . . . . . . . . . . . . . . . .
3.3.1 The labor market . . . . . . . . . . . . . . . . . . . . . . .
Labor income . . . . . . . . . . . . . . . . . . . . . . . . .
3.3.2 The capital market . . . . . . . . . . . . . . . . . . . . . .
Capital income . . . . . . . . . . . . . . . . . . . . . . . .
3.3.3 The land market . . . . . . . . . . . . . . . . . . . . . . .
3.3.4 Enterprise income . . . . . . . . . . . . . . . . . . . . . .
3.3.5 Household income . . . . . . . . . . . . . . . . . . . . . .
Regional households . . . . . . . . . . . . . . . . . . . . .
Labor out-migration households . . . . . . . . . . . . . .
Labor in-migration households . . . . . . . . . . . . . . .
3.4 Measures of regional and household welfare . . . . . . . . . . . .
3.4.1 Regional welfare . . . . . . . . . . . . . . . . . . . . . . .
Gross regional product . . . . . . . . . . . . . . . . . . . .
Regional expenditure . . . . . . . . . . . . . . . . . . . . .
Regional price level . . . . . . . . . . . . . . . . . . . . . .
Net government revenue . . . . . . . . . . . . . . . . . . .
Other regional measures of welfare . . . . . . . . . . . . .
3.4.2 Household welfare . . . . . . . . . . . . . . . . . . . . . .
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Household income . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Compensating and equivalent variation . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Model Execution
4.1 Competitive CGE model equations
4.2 GAMS Solution . . . . . . . . . . .
4.3 Model construction in GAMS . . .
4.4 Model simulation . . . . . . . . . .
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5 Increasing Returns and Imperfect Competition in Regional CGE Modeling
5.1 Increasing returns, non-convexity, and competitive CGE models . . . . . . . . . .
5.2 Modeling increasing returns and imperfect competition . . . . . . . . . . . . . . .
5.2.1 Increasing returns -- the dual approach . . . . . . . . . . . . . . . . . . .
5.2.2 Increasing returns -- the primal approach . . . . . . . . . . . . . . . . . .
5.2.3 Market power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Contestable pricing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
From monopoly to oligopoly . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 5.3 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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6 Policy Applications and Summary and
6.1 Policy applications . . . . . . . . . . .
6.1.1 Agricultural export prices . . .
6.1.2 Sport fishing trip demand . . .
6.2 Summary and conclusions . . . . . . .
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Conclusions
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References
46
List of Tables and Figures
2.1 Aggregated Social Accounting Matrix(SAM) for Oklahoma, 1993($1,000) or pdf file of
and Tables 2-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.1 Elasticities of Import Substitution . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3.2 Elasticities of Transfformation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Competitive CGE Model Equations . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.2 Subscript Notation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.3 Summary of Endogenous Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.4 Summary of Exogenous Variables . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.5 Summary of Parameterss . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.6 Effects of a 5% Change in Terms of Trade, Oklahoma, 1993 . . . . . . . . . . . . . .
Figure 2.1 An Illustrative Social Accounting Matrix . . . . . . . . . . . . . . . . . . . .
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Table 2.1
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List of acronyms
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Glossary of Terms
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7
1
1.1
Introduction
Introduction
Partial equilibrium analysis illustrates results for one market at a time. However, there often exist market
interactions and thus market feedbacks. As Nicholson suggests, pricing outcomes in one market usually have
effects in other markets, and these effects, in turn, create ripples throughout the economy, perhaps even to
the extent of affecting the price-quantity equilibrium in the original market. To represent this complex set of
economic relationships, it is necessary to go beyond partial equilibrium analysis and construct a model that
permits viewing many markets simultaneously. The general equilibrium model is a framework for analyzing
linkages between markets and thus interactions between industries, factor resources and institutions.
de Melo and Tarr argue that inter-industry linkages are best captured in a general equilibrium framework.
Although partial equilibrium may yield accurate estimates for particular sectors, estimates of aggregate costs
of regional policies across sectors, for example, require a general equilibrium model to account for region-wide
budget and resource constraints.
In the past, implementation of general equilibrium analysis was constrained by inadequate data and computational resources. Currently, however, the existence of large-capacity computer technology has made possible
applications of such models to actual market situations. By recommending general equilibrium analysis, we
do not mean that econometric estimates representing different sectors have little value. Rather, the two
approaches should be viewed as complementary because it is neither feasible nor desirable to estimate, as a
system of simultaneous equations, the full set of conditions describing a multisector economy model (de Melo
and Tarr). In many cases, general equilibrium analysis borrows parameter estimates from partial equilibrium
econometric studies.
1.2
General equilibrium economic models
Several approaches have been used to represent the regional macroeconomy interactions among sectors and,
hence, the analysis of impacts of alternative policies. Most general equilibrium procedures are broadly
categorized into fixed-price (multiplier) impact analysis and the endogenous price, quantity and income
computable general equilibrium (CGE) methods. This section provides an overview and comparison of these
model types and their variants.
Input-output analysis, attributed to Leontief, has been used for assessing the impact of a change in the
demand conditions for a given sector of the economy. The basic relationship in these models is represented
by
Xij = aij Xj ,
(1.1)
where Xij , the amount of sector i’s output required for the production of sector j’s output, is assumed to be
proportional to sector j’s output Xj , and aij is the relevant input-output coefficient. Summing over sectors
and adding final demand Fi to equation (1.1) produces the I-O model:
Xi =
π
X
aij Xj + Fi ,
(1.2)
j=1
which is also assumed to hold in first-difference form (depicting changes in the variables). An increase in
final demand in a particular sector by, say, ∆Fi will initially increase production for that sector, which in
turn raises the intermediate demand for all sectors. To produce these intermediate inputs, however, more
intermediate inputs are required. Although sectoral outputs keep on rising in several rounds, these increases
become smaller and smaller such that their total always has a limit (Sadoulet and de Janvry). Equation (1.2)
is often written in matrix notation:
X = (I − A)−1 F,
(1.3)
where X is the vector of outputs, F is the vector of final demands, A is the matrix of input-output coefficients,
and I is the identity matrix (with ones on the diagonal and zeros elsewhere). The matrix (I − A)−1 represents
a multiplier used to calculate overall changes in sectoral outputs caused by changes in final demand. For a
more complete discussion of input-output see the web text chapter by William A. Schaffer.
8
Input-output analysis hinges on the crucial assumption that sectoral production is completely demand-driven,
implying that there is always excess capacity in all sectors that is capable of meeting increased demand with
no price increase. Because this assumption is likely to be unrealistic, input-output models are more useful as
guidelines to potential induced linkage effects, and as indicators of likely bottlenecks that may occur in a
growing economy, than as predictive models (Sadoulet and de Janvry).
Further, I-O models assume a constant returns to scale production function with no substitution among
the different inputs. Prices are also assumed constant, which is not a major problem as substitution among
factors is expected to be induced only by nonexistent relative price movements.
Extension of the I-O model to a social accounting matrix (SAM) framework is performed by partitioning
the accounts into endogenous and exogenous accounts and assuming that the column coefficients of the
exogenous accounts are all constant. According to Sadoulet and de Janvry, endogenous accounts are those for
which changes in the level of expenditure directly follow any change in income, while exogenous accounts are
those for which we assume that the expenditures are set independently of income. In determining exogenous
accounts, it is common practice to pick one or more among the government, capital, and the rest of the world
accounts based on macroeconomic theory and the objectives of the study.
Although I-O and SAM models have typically been used for impact analyses, they do not consider the special
case where productive capacity of a sector is curtailed or eliminated (Seung, et al.). This concern has led
to the emergence of mixed exogenous/endogenous I-O models where the production capacity of a sector is
exogenously reduced (Petkovich and Ching). To examine the impacts of timber production potentials on
income distribution, Marcouiller, Schreiner and Lewis (1993) demonstrated an application of a SAM version
of the mixed exogenous/endogenous model, the supply-determined SAM (SDSAM) model, to the analysis of
forest products.
However, these mixed exogenous/endogenous models, though relatively easy to implement, have limitations
similar to fixed-price models. These are fixity of prices and no factor substitution in production and no
commodity substitution in consumption. Seung et al. contend that, by these restrictive assumptions, the
SDSAM model lacks microtheoretic foundation. Thus, such models are internally inconsistent because outputs
for some sectors are forced to be fixed and final demands for the same sectors are assumed endogenous.
To circumvent the limitations posed by the SDSAM model, regional economists have turned to using the more
theoretically sound computable general equilibrium (CGE) models as a tool for policy and impact analyses.
In CGE analysis, output in all sectors is endogenously determined and prices are assumed sufficiently flexible
to clear the commodity and factor markets. An empirical comparison of the SDSAM and CGE approaches
by Seung et al. indicates that, compared to the CGE model, the SDSAM model tends to overestimate
the policy impacts and to estimate production decreases in sectors where production may not change or
may increase. The authors conclude that a regional CGE model is theoretically more sound than mixed
exogenous/endogenous fixed price models for impact analyses where productive capacity of sectors is curtailed
or eliminated.
Partridge and Rickman argue that fixed-price regional models are limiting cases of the more general Walrasian
general equilibrium system. In fixed-price models, which are characterized by perfectly elastic supply, the
total change in the regional economy is always predicted to be proportionate to the exogenous change. The
Walrasian general equilibrium procedure, which is grounded in neoclassical theory, specifies less than elastic
supply with equilibration of demand and supply achieved through flexible prices. In these models, the total
response in an economy to an exogenous change is not necessarily proportionate and depends upon the
various elasticities of demand and supply.
9
2
Overview of CGE Analysis
The CGE framework offers an alternative for regional analysis. It encompasses both the I-O and SAM
frameworks by making demand and supply of commodities and factors dependent on prices. A CGE model
simulates the working of a market economy in which prices and quantities adjust to clear all markets. It
specifies the behavior of optimizing consumers and producers while including the government as an agent
and capturing all transactions in circular flow of income (Robinson, Kilkenny and Hanson).
In the Walrasian neoclassical general equilibrium approach, the main equations are derived from constrained
optimization of the neoclassical production and consumption functions. Producers are assumed to choose
their level of operation so as to maximize profits or minimize costs using constant returns to scale production
technology. Production factors – labor, capital and land – are all paid in accordance with their respective
marginal productivities. Consumers are assumed to choose their purchases to maximize their utility subject to
budget constraints. At equilibrium, the model solution provides a set of prices that clears all commodity and
factor markets and makes all the individual agent optimizations feasible and mutually consistent (Bandara).
CGE analysis has been applied to a wide range of policy issues, which include, among others, income
distribution, trade policy, development strategy, taxes, long-term growth and structural change in both
developed and less developed countries (LDCs). Dixon and Parmenter associate the proliferation of these
models in LDCs with two major conditions. First, growing realization that CGE models, unlike a number
of other types of economic models, allow the simulation of policy alternatives in a way which is readily
understood and perceived to be both relevant and useful by policy makers. Second, vast progress in the
development of user friendly, readily transferable high capacity computer software, which has greatly increased
researchers’ ability to handle models with considerable detail.
2.1
CGE analysis at national and regional levels
Most CGE models have been used to capture the effects of policies and economic shocks at the national level.
Application of the technique to regions (such as states) is more recent. Examples of regional applications in
Oklahoma include Koh, Lee, Budiyanti, and Amera.1
Regional CGE models differ from their national counterparts in several respects. Most of these differences
stem from the fact that regions are relatively more open economies compared to nations. Because of regional
openness, commodity trade and resource migration are more important in regional CGE models. For example,
regional households and entrepreneurs would not invest within the region if other regions offered higher
rates of return. Thus, while national CGE models require that savings be equal to investment, regional
CGE models permit excess savings to flow out of the region and vice-versa. This is not to say that regional
policymakers cannot influence rates of return to investments but that control over major components of
monetary policy is mainly determined at the national level.
In general, CGE models require considerable data, which, in most cases, is difficult to obtain. This problem
is more severe at the regional level, where data in most cases is virtually non-existent. In fact, one of the
possible reasons for the relatively slow start of regional CGE modeling is the paucity of regional data, in
addition to unresolved theoretical issues of regional specification 2 (Partridge and Rickman). Most of the
limitations of regional CGE models are also inherent in alternative empirical regional modeling, such as I-O,
SAM, and econometric.
Although regional CGE models have grown in popularity in recent years as an alternative method for
examining regional economies and policy issues, their contribution has yet to be assessed. Partridge and
Rickman present an extensive review of literature related to regional CGE modeling and conclude that
regional CGE models, though still with unclear conclusions on issues of quantitative accuracy, represent a
significant advancement in regional economic analysis. For details on the current state of the art of regional
CGE modeling, readers are referred to Partridge and Rickman.
1 These are all Ph.D. studies completed at Oklahoma State University. Results of the studies have been published in Koh,
Schreiner and Shin; Schreiner, Lee, Koh, and Budiyanti; and Amera and Schreiner. Partridge and Rickman give an extensive
review of many other regional studies.
2 Issues of functional form, elasticity specification, closure rules, sensitivity analysis, market structure, and dynamics.
10
The greater openness of regional economies suggests some desired divergence in structure between national
and regional CGE models. In spite of the differences between national and regional CGE models discussed
above, the general formulation used in most studies is basically the same. While some studies have been
designed to capture the added complexity, others have relied on the specifications common to the national
CGE literature.
Most empirical applications of CGE models have been developed on the simplifying assumption of constant
returns to scale production technology and perfectly competitive market structures. This has made these
models fail to adequately represent industries with declining unit cost structures. Recently, de Melo and
Tarr used the theory of duality to develop and apply a production modeling technique that accommodates
imperfect competition in the U.S. auto and steel industries. Tembo has suggested and demonstrated an
application of this technique to regional economies. Vargas and Schreiner show an application to monopsony
markets in the regional timber industry.
The purpose of this chapter is to present and illustrate application of the salient features of the regional CGE
model and to provide a step-by-step example of their empirical implementation. In this endeavor, the more
traditional perfectly competitive constant returns to scale version of the CGE model is presented first. This
is then followed by a variation that accommodates imperfect competition (see section 5.0).
2.2
Data and data organization
CGE models are very data intensive. Thus, the first step in implementation of a CGE model is identification
and organization of data into a social accounting matrix (SAM). The SAM is a square matrix representing a
series of accounts which describe flows between agents of commodity and factor markets and institutions.
It is a double-entry book-keeping system capable of tracing monetary flows through debits and credits and
constructed in such a way that expenditures (columns) and receipts (rows) balance. King distinguishes two
objectives for the SAM: 1) to organize information about the economic and social structure of a country,
region in a country, city or any other geographic unit of analysis; and 2) to provide a “fixed point” basis for
the creation of a plausible model.
Regionalized economic datasets that can serve as a basis for regional CGE models are now available. This
section describes the types of data required for building regional CGE models. These data needs include
regional social accounts and parameters required for incorporating economic relationships among industries,
in production and factor usage, among institutions, and in the generation of regional economic output. Each
is addressed in-turn in the following sections.
2.2.1
Social accounting matrices
The base data upon which a regional CGE model is constructed relies on a static accounting for economic
transactions taking place in a base year and specific to the region under examination. Input-output (I-O)
tables provide one data framework but lack the comprehensive accounting of income flows. Base data on these
income flows are necessary to address labor components, production structures, and government interaction
necessary to conduct policy analysis. A more comprehensive accounting structure for regional economies is
provided through an I-O extension known as a social accounting matrix (or SAM.) SAM extensions were
initially developed during the late 1960’s and early 1970’s as a result of general dissatisfaction with the
manner in which income flows were treated. A good overview of SAM development and analytical background
for the interested reader can be found in Pyatt and Round and Hewings and Madden. SAMs as a basis for
CGE models is addressed in Isard et al.
What is a SAM?
Like input-output accounts, social accounting matrices provide a comprehensive accounting structure of
regional market-based productive activities and utilize similar double-counting book-keeping entries. Unlike
input-output, however, social accounts focus on the household as the relevant unit of analysis and provide a
comprehensive, and additional, set of accounts that track how household income is generated and distributed.
Where input-output tables are focused on industries and their respective relationships with regional output,
11
SAMs extend this into a more complete range of market mechanisms associated with generating household
income. The relevant focus thus shifts from how regional output is produced to also address how regional
income is generated and distributed. This comprehensive element is particularly important in regional CGE
models that focus on both production processes and the economics of household factor supply, commodity
demand, and government interaction.
How are SAM’s useful for policy analysis?
Social accounting matrices have been employed in a wide array of situations arising in policy development to
address key issues of economic structure and impact assessment. A good overview of SAM applications in
policy analysis was written by Erik Thorbecke and found in the recent text by Isard et al. (pages 317-331.)
Basically, SAMs are useful in assessments that require a more comprehensive accounting of circular flows of
an economy.
Particularly useful for addressing issues of income distribution, SAMs have been widely employed in assessing
development effectiveness in attaining equity-based outcomes of policy. Applications, however, are not limited
to assessing redistributive income policies. This is particularly true in the United States as national and state
level policies that support the redistribution of income to the poor are largely out of favor. Increasingly,
welfare reform legislation has emphasized the role of private markets to provide for individual welfare. SAMs
have been employed to assess the relative impacts of alternative market-based changes on the distribution
of income within regions. Thus SAMs will continue to be relevant tools to address a wide array of policy
situations and development issues.
The major strength of regional SAMs include accounting comprehensiveness. Although still widely used,
it is important to note that SAMs have some rather serious theoretical shortcomings when used to model
economic change. These modeling caveats have, in part, driven the movement toward developing more flexible
modeling systems. As such their use in computable general equilibrium models remains the focus of this
chapter.
How is a regional/state SAM constructed?
SAMs can be constructed in a variety of ways. The manner in which a SAM is specified is typically driven by
the problem being addressed. A thorough assessment of the various types of SAM structures is beyond the
scope of this chapter. Rather, for this discussion a generic SAM structure will be discussed illustrated by a
modest empirical SAM constructed for the Oklahoma economy.
Data elements for constructing a SAM. An illustrative SAM framework is provided in Figure 2.1. From an
input-output perspective, the rows and columns that correspond to industry and commodity are the focus.
Whereas input-output is limited to this industrial perspective, social accounting matrices extend the dataset
to more fully capture income distribution resulting from returns to primary factors of production (land,
labor, and capital.) In this way, the circular flow of goods and services to households from firms and the
corresponding factor market flows to firms from households are captured.
In the SAM, row totals and column totals are equal thus representing a regional economy in equilibrium.
For example, total industry output just equals the outlay used in its production. Institutional income (to
households for example) just equals the outlay required for the use of institutionally-owned land, labor,
and capital in the factor markets. In general, total income equals total cost of inputs. SAM accounts are
constructed to balance outputs with inputs.
Data sources for SAM building. Once again, the specific data requirements for constructing a regional
SAM vary depending on the type of problems being addressed. However, some generalizations can be
made. In addition to standard input-output data (industry production, interindustry transactions, final
demands, factors of production and imports/exports), typical SAMs require additional data on total factor
payments, total household income (by income category), total government expenditures and receipts (including
intergovernmental transactions), institutional income distribution, and transfer payments (both to households
and to production sectors.) SAMs are typically built as static snapshots of a region thus, data elements will
need to be generally consistent in temporal and geographic specificity.
12
Industry
Industry
(detail)
Figure 2.1 An Illustrative Social Accounting Matrix
Commodity
Factors
Institutions
Gov’t
Make
Commodity
(detail)
Use
Factors
-land
-labor
-capital
Returns to
Primary
Factors
(value
added)
Institutions
-households
-other
Government
Sales
Sales
Indirect
Business
Taxes
Imported
Purchased
Inputs
Total
Industry
Outlay
Sales Tax
Trade
TOTAL
2.2.2
Consumption
Distribution
of factor
Income
Factor
Taxes
Imports
Imports
Total
Commodity
Outlay
Total
Factor
Outlay
Exports
Output
Transfer
Payments
Intergovernmental
Transfers
Total
Institutional
Outlay
Trade
Total
Gov’t
Outlay
Exported
Primary
Factors
(e.g.
labor
flow)
Exports
TOTAL
Total
Industry
Output
Total
Commodity
Total
Factor
Income
Total
Institutional
Income
Total
Government
Income
TransTotal
shipments imports
Total
Exports
Using IMPLAN to construct a SAM
For purposes of illustration, discussion will center on a readily available dataset for the initial regional static
equilibrium. A good example of this base economic equilibrium data is found in the county-level files available
from the Minnesota IMPLAN Group (or MIG.)3 This consultancy group develops relational datasets built
from secondary data available at the national, state, and county-level from the BEA REIS, BLS ES202,
County Business Patterns and other sources. Specifically, this group first gathers data at the national level,
converts it to a standardized format, derives national input-output tables and national tables for deflators,
margins and regional purchase coefficients. State level data is gathered and controlled totaled to the national.
County level data is gathered and controlled totaled to each state. County or regional-level input-output
tables are derived using various data elements employed in the model development software embedded within
IMPLAN Pro.
Over the course of development, the Minnesota IMPLAN Group has endeavored to adapt, expand, and extend
datasets into more comprehensive accounting structures and regional modeling approaches. For example, a
set of social accounts has been added to the county-level IMPLAN datasets. These accounts are available for
use both in assessing inter-institutional transactions and in regional CGE modeling. The latter application
has been under development for the past few years. Notable discussions of these developments can be found
in Robinson and Sullivan, McCollum, and Alward.
Specific data incorporated into the IMPLAN SAM begins with standardized elements of the National Income
and Product Accounts (NIPA.) Household transfer payments and distributional breakdowns come from the
Census of Population, BEA REIS dataset and the BLS Consumer Expenditure Survey. Government data
requirements originate from the Annual Survey of State and Local Government Expenditures. This data
source provides state and local revenues and expenditures by detailed category.
3 The IMPLAN Pro software and county/state datasets are available from the Minnesota IMPLAN Group (accessed on the
world wide web at www.implan.com.) Their mailing address is 1725 Tower Drive West, Suite 140, Stillwater, MN 55082, Voice:
651/439-4421 Fax: 651/439-4813.
13
Generating a SAM from an IMPLAN model is rather straightforward given general knowledge of software
and dataset operations. The SAMs generated from IMPLAN are not, however, without drawback. One key
drawback of using the IMPLAN system to generate a social accounting matrix is the rather rigid categorization
scheme used in dataset and model construction. For example, due to the manner in which the dataset was
developed, value added remains in rather nebulous categories that match published secondary data sources.
Instead of value added being separated into returns to land, labor, and capital, value added in IMPLAN is
reported in categories that include employee compensation, other property type income, proprietary income,
and indirect business taxes. One ad hoc method of conversion is to simply use employee compensation as a
proxy for labor returns (which neglects proprietary income), other property type income as a proxy for land
returns, and proprietary income as a proxy for capital returns (actually more a mixture of labor and capital
returns). Although there exist procedures for disaggregating total value added into more standard categories
of factor return, these methods tend to be data intensive and complex.
The aggregate SAM for Oklahoma
The number of sectors represented in the SAM and, hence, the number of markets in the CGE model depends
to a large extent on the purpose of the study. Budiyanti, for example, aggregated the Oklahoma 1991 SAM
to 14 industrial sectors of market goods, two sectors of non-market goods, three value-added sectors (capital,
labor, and land), and three institutions (enterprises, households and government). The labor sector was
further sub-divided into five skill levels. The household sector was also divided into low-, medium- and
high-income classes. Government was represented by a state/local level and a federal level. Amera’s 1993
Oklahoma SAM has 30 industrial sectors, three factor sectors, three household sectors, two government
sectors, one enterprise sector, one investment sector, and a rest-of-the-world sector. For illustration purposes
in this chapter, a highly aggregated (four-industrial sector) version of Amera’s SAM is used as the data source
(Table 2.1). This SAM also aggregates the household and government sectors into one sector each.
2.3
Determining parameter values
Once the economic agents are identified and their optimizing behavior specified by algebraic equations, the
parameters in those equations must be evaluated. Data on endogenous and exogenous variables obtained
at a snapshot point in time are typically used for this purpose. This process is referred to as calibration .
Calibration or benchmarking determines the values of the normalizing (or free) parameters so as to replicate
the observed flow values incorporated in the SAM (de Melo and Tarr). This process assumes that all equations
describing market equilibriums in the system (model) are met in the benchmark period.
When dealing with flexible functional forms, such as the constant elasticity of substitution (CES) or the
constant elasticity of transformation (CET), it is necessary to supplement the calibration process with these
exogenously determined elasticities.4 Other parameters obtained from literature (econometric studies) include
income elasticities, migration elasticities, and price elasticities of export demand. These parameters are used
to illustrate the calibration process of the various components of the regional CGE model.
The calibration process starts with choice of units. Because in CGE analysis only relative prices matter, all
prices and factor rents are normalized to unity in the initial equilibrium. With prices normalized to one,
then the flow “values” in the SAM (Table 2.1) may be interpreted as a physical index of quantity in the
commodity (industry) and factor markets (click here for further explanation of normalized prices). Once all
the parameters are specified, the model is solved to reproduce the benchmark data. The solution obtained
with the benchmark data is referred to as the “replication” equilibrium, assuming the benchmark represents an
equilibrium outcome, given existing exogenous conditions (Partridge and Rickman). In addition to providing
a check on the accuracy of the calibration, the replication also shows that the complete circular flows of
income and expenditures are balanced, which is referred to as microconsistency of the data. Counterfactual
equilibria are obtained by introducing shocks to exogenous variables, changes in market conditions, or changes
in any policy variable and rerunning the model. The general algebraic modeling system (GAMS) software is
used for solving the regional CGE model. The following sections in this paper outline the general features
4 Application
of these elasticities in the CGE framework are discussed in chapter3.
14
of a regional CGE model and demonstrate the calibration and solution processes under both perfect and
imperfect competition.
15
3
A Competitive Regional CGE Model
In a market economy there is generally a large number of homogeneous goods and services, which include
not only consumption items but also factors used in production. Each of these goods and services has a
market price, determined by the forces of supply and demand. Every market is assumed to clear at this
set of prices. The perfectly competitive model further assumes zero transactions cost, a large number of
price taking market participants (consumers and suppliers), and existence of perfect information, all of which
support the law of one price (Nicholson).
Under these conditions, computable general equilibrium (CGE) models are similar to multimarket models, in
which agents’ decisions are price responsive and markets reconcile supply and demand. Because they also
encompass macroeconomic components, such as investment and savings, balance of payments and government
budget, they are best chosen for policy analysis when the socioeconomic structure, prices, and macroeconomic
phenomena all prove important (Sadoulet and de Janvry). CGE models have been built to simulate the
economic and social impacts of various scenarios. Examples of alternative scenarios include foreign trade
shocks, changes in economic policies, and changes in domestic economic and social structure.
In a regional CGE model, production creates demand for value-added factors and goods and services used as
intermediate inputs. Intermediate inputs consist of both imports and locally produced goods and services.
Demand for value-added factors interacts with available factor supplies to determine factor prices. Margins,
such as taxes and transportation costs, increase factor costs to firms, which in turn increase product prices.
Factor rates of return and ownership of factor supplies determine personal income, which in turn influences
demand for imports and locally produced goods and services. Equilibrium occurs at prices which equate the
demands for goods and services with supplies, and the demands for factors with factor supplies.
Because the CGE model attempts to look at all adjustments simultaneously, it is inherently an extensive
formulation. To enhance understanding by students and prospective users of CGE analysis, the model here
is split into components and each component is explained separately. The components include commodity
markets, factor markets, production systems, institutional agents, and welfare measures.
3.1
Production system
Unlike regional input-output and SAM models, which are based on Leontief technology, neoclassical theory
guides specification of production in regional CGE models. In consequence, the CGE model does not represent
factor demands as linear functions of output. Instead, factor demands depend on both output and relative
prices. The only exception, however, is in relation to treatment of those goods and services that are used
as intermediate inputs. The Leontief input-output production function is used to represent production of
regional output with fixed proportions of composite primary factors and composite intermediate inputs.
The composite primary factors generally enter the production process in a manner allowing factor substitution.
Thus, production is best described as a multi-level or nested production process. Note that all factors in a
constant elasticity of substitution (CES) function have the same elasticity of substitution between any pair of
factors. To allow for differing elasticities between sets of factors, multi-level or “nested” production function
forms are used in CGE, with each level containing a different set of factors and their own corresponding
elasticities of substitution. That is, the use of a multi-level structure allows for use of both fixed-coefficients
and price responsiveness in the CES form.
3.1.1
Composite value-added and intermediate inputs
The Leontief input-output production function that represents the on- substitutability between intermediate
and primary inputs constitutes the first level of the three-level production process characteristic of most CGE
models. For a single industry/sector, the Leontief production function is presented as:
V A i Vi
(3.1.1)
,
Xi = min
a0i a1i
where Xi is gross output of sector i, V Ai is composite factor (value-added) inputs of industry i and Vi
is composite intermediate inputs of industry i. Constants a0i and a1i represent industry i’s input-output
16
coefficients for composite factor inputs and composite intermediate inputs.
By rearranging terms in equation (3.1.1), the (input-output coefficient) parameters of the Leontief production
function are calibrated as follows:
V Ai
, and
Xi
Vi
=
Xi
a0i =
a1i
(3.1.2)
For each calculation in equation (3.1.2), values of the variables on the right-hand-side (RHS) are given
in the SAM. For the agricultural sector in Table 2.1, for example, total output Xi = 4, 344, 160, 000 (the
column or row total), composite factor inputs V Ai = 1, 713, 668, 000, and composite intermediate inputs
(locally produced plus imports) Vi = 2, 534, 191, 000. Therefore, Leontief parameter values are a0i = 0.40 and
a1i = 0.58 (click here for graphic presentation of Leontief production function). Although an industry is an
aggregation of many producers, it is treated as a single firm in the CGE framework.
3.1.2
Substitution among primary factors of production
What generally distinguishes a regional CGE production structure from a simple input-output model is that
value-added (primary) factor usage is responsive to factor costs, and imports of intermediate goods are price
responsive (Partridge and Rickman). At the second level of production, nesting allows different treatment of
intermediate goods from that of value-added factors.
Primary inputs and their demands
Cobb-Douglas (CD) or constant-elasticity-of-substitution (CES) functions are commonly specified to represent
substitution among primary factors of production in a sector - land, labor, and capital. Here production
technology is assumed to possess constant returns to scale (CRS). The CD function implicitly specifies
unitary factor substitution elasticities, while the CES is a more general case that allows different from unitary
elasticities of substitution. For simplicity, the Cobb-Douglas functional form is used to represent the second
level of production:
αL
V Ai = φVi A LABi i
•
αK
i
CAPi
•
αT
LAN Di i , (αiL + αiK + αiT ) = 1
(3.1.3)
where LABi , CAPi , and LAN Di are labor, capital, and land inputs for industry i, respectively. Coefficient
φVi A > 0 is the total factor efficiency parameter for composite primary factor inputs in sector i. Parameters
αiL , αiK , and αiT are production elasticities (click here for CD production elasticities) and correspond to
labor, capital and land, respectively. Constant returns to scale are imposed by assuming that the sum of the
elasticities in equation (3.1.3) is equal to unity. Individually, the production parameters are also assumed to
have values that lie between zero and one. By substituting and rearranging terms in equations (3.1.2) and
(3.1.3), sectoral gross output (Xi ) can be expressed in the Cobb-Douglas production function form:
Xi =
φVi A
αK
αL
αT
LABi i • CAPi i • LAN Di i ,
α0i
or
αL
i
Xi = φX
i LABi
•
αK
i
CAPi
•
αT
LAN Di i , where φX
i =
(3.1.4)
φVi A
α0i
(3.1.5)
Assuming that labor, land, and capital are the only value-added (or primary) inputs in the production of
sector i’s output Xi , the sector’s profit function is
πi = P Ni • Xi − P L • LABi − P Ki • CAPi − P T • LAN D,
(3.1.6)
where πi is profit (click here for example of profits) for sector i, P Ni is net price of output (i.e. output price
less cost of intermediate inputs and indirect business taxes), P L is wage rate, P Ki is capital rent (assuming
capital is fixed by sector), and P T is land rent.
17
Assuming all firms in the sector strive to maximize profits, differentiating equation (3.1.6) with respect to
each of the inputs and equating the outcome to zero will give the first order conditions. Thus, the first order
condition with respect to capital is:
∂Xi
∂πi
= P Ni
− P Ki = 0
∂CAPi
∂CAPi
(3.1.7)
Rearranging terms in equation (3.1.7), the marginal product of capital is equal to the ratio of capital rent to
output net price:
P Ki
∂Xi
=
.
(3.1.8)
∂CAPi
P Ni
Substituting equation (3.1.5) into equation (3.1.7) yields the following:
αK
αL
i •
CAPi i
∂(φX
∂πi
i LABi
= P Ni
∂CAPi
∂CAPi
•
αT
LAN Di i )
− P Ki = 0
(3.1.9)
− P Ki = 0
(3.1.10)
which translates into:
αK
i
αL
αK φX LABi i • CAPi
∂πi
= P Ni i i
∂CAPi
CAPi
•
αT
LAN Di i
Rearranging terms in equation (3.1.10) and substituting for Xi using equation (3.1.5), yields an expression
for capital’s share parameter in the Cobb-Douglas production function:
αiK =
P Ki • CAPi
P Ki CAPi
∗
, or αiK =
P Ni
Xi
P Ni • X i
(3.1.11)
This is equivalent to multiplying capital’s marginal product (see equation 3.1.8 above) by the ratio of capital
to output, which is also the formula for elasticity. Therefore, expression (3.1.11) shows that factor shares are
equal to production elasticities in a Cobb-Douglas function. Share parameters for labor and land are derived
in a similar fashion. In equation (3.1.11), making CAPi the subject of the formula yields the conditional
demand (i.e. fixed output level) for capital in the industry, given by:
CAPi =
αiK P Ni • Xi
P Ki
(3.1.12)
Similarly, conditional demands for labor and land can be expressed as:
LABi =
αiL P Ni • Xi
, and
P Li
(3.1.13)
αiT P Ni · Xi
(3.1.14)
PT
Calibration of the Cobb-Douglas production equation (3.1.5), involves determining and evaluating two sets of
parameters – share parameters and the efficiency parameter, where all prices are normalized to one. The
numerator and denominator in equation (3.1.11) are provided in the SAM as total capital returns and total
value-added, respectively. For the agricultural sector in the above SAM (Table 2.1), capital returns and
total value-added are $571,360,000 and $1,713,668,000, respectively. Substituting these values into (3.1.11)
yields αiK = 0.333. Similarly, αiL = 0.253 and αiT = 0.414. The efficiency parameter for the Cobb-Douglas
production function is calculated by rearranging equation (3.1.5):
LAN Di =
φCX
=
i
Xi
αL
LABi i
•
αK
i
CAPi
•
αT
(3.1.15)
LAN Di i
Calibration of equation (3.1.15) proceeds by substituting the calibrated factor share parameters and the
quantities for the factor variables obtained from the SAM. For the agricultural sector, φCX
= 7.46. Multiplying
i
φCX
by aoi yields the value φVi A . (Click here for graphic presentations of the calibrated production function
i
and factor demands).
18
Intermediate inputs and their demands
By the Armington assumption (Armington), goods produced in different regions (and possibly countries) are
assumed to be imperfect substitutes, usually specified as a constant elasticity of substitution (CES) function.
These intermediate goods from different regions combine at the second level of production to form composite
intermediate goods that enter the first level of production. The CES function representing the relationship
between the two categories of intermediate inputs can be expressed as:
ρV
ρV
V
V
V
Vji = φVji [δji
V Mjij + (1 − δji
)V Rjij ]1/ρj , ρVj =
σjV − 1
σjV
(3.1.16)
V
where φVj > 0 is the intermediate input efficiency parameter, 0 < δji
< 1 is the share parameter, V Mji
represents intermediate goods imported by sector i from sector j in the exporting region, V Rji is regionally
produced intermediate goods for sector i from sector j, σjV is the elasticity of substitution for industry j, and
φVj is the substitution parameter. The value of σjV depends on the degree of substitutability between the two
sources of intermediate inputs. If σjV = ∞, the two are perfect substitutes. If σjV = 0, they are used in fixed
proportions.
The following cost minimization problem is used to derive demand functions for regionally produced and
imported intermediate inputs:
Minimize P Mj • V Mji + P Rj • V Rji
ρV
ρV
V
V
V
Subject to: Vji = φVji [δji
V Mji1 + (1 − δji
)V Rji1 ]1/ρ1 ,
where P M and P R represent, respectively, prices of imported and regionally produced intermediate inputs
from sector j. Solving the first-order conditions of this problem and rearranging terms yields the following
expression:
σiV
V
1 − δij
P Mj
V Rji
.
(3.1.17)
=
V Mji
δji
P Rj
Calibration of this equation requires knowledge of the elasticity of substitution σjV and normalizing the
two prices, P M and P R to one. As stated above, values of elasticities of substitution are obtained from
other sources. For the Oklahoma agricultural sector, for example, manufacturing input has a value of 3.55
V
V
(Table 3.1). This leaves the share parameter δji
as the only unknown in equation (3.1.17). The value of δji
is calculated by substituting the elasticity of substitution and the base values for imported and regionally
produced intermediate inputs (from SAM) in the rearranged form of equation (3.1.17):
−1
1
V Rji σiV
V
.
(3.1.18)
+1
δji
=
V Mji
Table 3.1
Elasticities of Import Substitution
Sector
Parameter
Source
Agriculture
1.42
de Melo and Tarr
Mining
0.50
de Melo and Tarr
Manufacturing
3.55
de Melo and Tarr
Services
2.00
de Melo and Tarr
From the SAM, the known values for intermediate inputs from manufacturing to agriculture are V Rji =
V
159,671,000 and V Mji = 446,829,000. Thus, from equation (3.1.18), δji
= 0.359. The efficiency parameter is
computed by rearranging terms in the CES function (equation 3.1.16) and making the relevant substitutions:
Vji
φvji =
1/ρVi .
V
V
ρ
ρ
V V M i + (1 − δ V )V R i
δji
ji
ji
ji
19
(3.1.19)
Total intermediate inputs from manufacturing to agriculture is, Vji = 606,500,000 (see the SAM). Thus,
evaluating equation (3.1.19) yields the value φVji = 1.931 for the agricultural sector.(Click here for graphic
presentations of the substitution between the two sources of intermediate inputs).
3.1.3
Substitution among types of factor inputs
A third level in the nested production process may represent substitution among labor skills within the overall
labor input, among classes of land within the overall land input for agriculture, or types of capital inputs
within the overall classification of capital. (The SAM presented in Table 2.1 does not show subcategories of
primary inputs.) A common procedure is to consider the CES form of production which allows elasticities of
substitution to differ among industries but requires the elasticity of substitution among any two subcategories
(i.e. labor skills, land classes or types of capital) to be the same. Alternatively, subcategories could be
grouped into two parts, such as production labor and all other, with one elasticity of substitution between
the two and then two different classes of production labor with a different elasticity of substitution.
The elasticities of substitution for this level of the production process must come from other studies. (Click
here for modeling substitution among labor skills). The studies by Koh and Budiyanti classified labor into
five skill levels following work by Rose. They then assumed the Cobb-Douglas elasticity of substitution (equal
to one) for all combinations of skill levels and for all industries. No sensitivity analysis was completed to test
the results of varying these elasticities.
3.1.4
Net output price
Net output price in the competitive model is regional output price minus the unit cost of intermediate inputs
and unit value of indirect business tax:
P Ni = P Xi −
X
j
aji Pj − ibti P Xi
(3.1.20)
where P Ni is commodity i’s net price, P Xi is the composite regional output price, aji is the amount of the
j th commodity per unit output of the ith commodity, Pj is the composite purchase price of the j th comodity,
and ibti is the indirect business tax per unit value of output. (See section 3.2.4 for explanation of composite
regional output price and composite purchase price). The net output price is the per unit value of output
available to compensate for primary factor use. Under conditions of constant returns to scale in production,
the sum of the marginal value products for all primary factor use should exactly equal the commodity net
price.
3.2
Commodity markets
Commodity trade involves both regional and export markets. Within the region, commodity supplies are
obtained from regional sources (regional production sectors) as well as from out-of-region sources (imports).
Though differentiated by source, these commodities are bought by industries (intermediate inputs), households
and other institutions. Inter-industry commodity flows have been discussed in Section 3.1 as intermediate
input demands. In this section, we discuss regional output markets and household commodity demand
systems.
3.2.1
Market outlets for regional output
Each industry in the region produces a composite commodity that can be exported or sold in the regional
market. Export markets include other regions within the country and international markets. In CGE analysis,
exports and regionally sold products are assumed to be differentiated by market, with the relationship between
them represented by a constant elasticity of transformation (CET) function. Price ratios and elasticities of
20
transformation determine the levels of output exported and sold in the region. The substitution possibilities
are, thus, represented as
Xi =
φX
i
1/ρX
i
σiX + 1
ρX
ρX
X
X
i
i
∂i EXPi + (1 − ∂i )Ri
, ρX
i =
σiX
(3.2.1)
X
where Xi is industry i’s total output (as defined above), ρX
i > 0 is the output efficiency parameter, 0 < ∂i < 1
is the share parameter, EXPi represents sector i’s supply for export, Ri is the sector’s output supply to
the regional market, σiX is the elasticity of transformation for industry i, and σiX is the output substitution
parameter. The value of σiX depends on the degree of transformability between the two market outlets. If
σiX = ∞, the two are perfect in their transformation. If σiX = 0, the two markets are not substitutable and
further market behavior for each must be specified (see Berck et al. for an alternative to the CET).
Each firm allocates it’s output between the regional and export markets so as to maximize revenue, subject to
the CET function. Because the production process is assumed the same for each market, revenue maximization
may be substituted for profit maximization. Thus, for given regional and export prices, the problem faced by
the firm is to:
maximize P Ei • EXPi + P Ri • Ri
1/ρX
i
ρX
ρX
X
X
X
i
i
,
subject to: Xi = φi ∂i EXPi + (1 − ∂i )Ri
where P Ei and P Ri are, respectively, prices of exported and regionally sold commodities from sector i.
Solving the first-order conditions and rearranging terms yields the following:
−σiX
1 − ∂iX
P Ei
Ri
=
.
(3.2.2)
EXPi
P Ri
∂iX
Calibration of this equation requires knowledge of the elasticity of transformation σiX , which is obtained from
other sources, and normalizing the two prices, P Ei and P Ri to one. For the Oklahoma agricultural sector in
Table 3.2, σiX = 3.90. The value of ∂iX , the only unknown in equation (3.2.2), is calculated by substituting
the elasticity of transformation and the benchmark values for exported and regionally sold commodities (from
SAM) in the rearranged form of equation (3.2.2):
Table 3.2
Elasticities of Transformation
Sector
Parameter
Source
Agriculture
3.90
de Melo and
Mining
2.90
de Melo and
Manufacturing
2.90
de Melo and
Services
0.70
de Melo and
− 1X
−1
σ
Ri
i
X
+1
∂i =
EXPi
Tarr
Tarr
Tarr
Tarr
(3.2.3)
For the agricultural sector (see SAM in Table 2.1), Ri = 1,752,557,000 and EXPi = 2,591,603,000. Thus,
from equation (3.2.3), ∂iX = 0.47. The efficiency parameter is computed by rearranging terms in the CET
function (equation 3.2.1) and making the relevant substitutions:
Xi
σiX =
1/ρX
(3.2.4)
i
X
X
ρ
ρ
∂iX EXPi i + (1 − ∂iX )Ri i
For the agricultural sector, Xi = 4,344,160,000 (see the SAM). Thus, evaluating equation (3.2.4) yields φX
i
= 2.01 for the agricultural sector. (Click here for graphic presentation of the calibrated CET function for
regional product and exports.)
21
3.2.2
Commodity consumption by households
Regional household income available for commodity expenditure is calculated as gross income minus government taxes, savings and, in this case, payments for labor employed by households. Equation (3.2.5) is an
algebraic representation of this relationship:
HEh = DYh − HSAVh − P L • LHh
(3.2.5)
where HEh is household expenditure, DYh is household disposable (minus government taxes) income, SAVh
represents household savings, P L is wage rate, and LHh is labor employed directly by households. The
subscript h represents household category (low, medium or high income). The current SAM (Table 2.1) shows
only total households.
The regional consumption by households is nested in two levels. At the first level, households maximize utility
from leisure and consumption of composite market commodities, subject to total time (work plus leisure),
household budget constraints and prices. At the second level, they choose optimal combinations of imported
and locally produced commodities, which are imperfect substitutes, so as to minimize their cost of purchasing
predetermined amounts of market commodities. Substitution between these commodity groups is captured in
a CES function. A detailed presentation of each of these levels of the household consumption follows below.
Household commodity demand systems
Several alternative formulations have been used to represent household demand systems in the literature.
Examples include the almost ideal demand systems (AIDS) by Deaton and Muellbauer, the Rotterdam
model by Theil, and Barten, and the linear expenditure system (LES) by Stone. In general, a theoretically
consistent demand system permits imposition of the general restrictions of classical demand theory. These
restrictions are a) adding-up: value of total demands equals total expenditure, b) homogeneity: demands
are homogeneous of degree zero in total expenditure and prices, c) symmetry: cross-price derivatives of the
Hicksian demands are symmetric, and d) negativity: direct substitution effects are negative for the Hicksian
demands.
The linear expenditure system is the most commonly used in CGE analysis due, in part, to convention and
because it allows representation of subsistence consumption, in addition to satisfying the above restrictions. In
this subsection, we provide an overview of the LES demand system and its adaptation to the CGE framework.
Readers interested in more detail about the LES and other demand systems are referred to Deaton and
Muellbauer.
In the LES, demand equations are assumed to be linear in all prices and incomes and the set of demand
functions is expressed in expenditure form:
pi qi = ci +
π
X
aij pj + βi y,
(3.2.6)
j=1
where pi is the price of the ith commodity, qi is the quantity of the commodity demanded, ci is the ith
intercept, aij are the price parameters, βi is the marginal budget share for the commodity, and y is the
household’s income. Empirically, the LES is derived from constrained maximization of the Klein-Rubin (also
known as Stone-Geary) utility function, whose general form is
X
X
U=
βi ln(Qi − γi ),
βi = 1
(3.2.7)
where U is the utility level, Qi is level of commodity i, βi is as defined above, and γi , if positive, is subsistence
minima as perceived by the consumer.
Given a fixed amount of household income that can be allocated to consumption, HEh , the household faces
the following constrained maximization problem:
π
P
Maximize U (Qih ) =
βih ln(Qih − γh )
i=1
22
subject to: HEh −
π
P
Pi • Qih = 0,
i=1
where the subscript h represents a particular category of households.5 Solving the first order conditions of
the Lagrangean to this problem produces the following results:
βih
= γPi , and
Qih − γih
HEh −
π
X
Pi • Qih = 0.
(3.2.8)
(3.2.9)
i=1
Rearranging terms in (3.2.8), summing across i, and solving for the Lagrangean multiplier yields
λ=
HEh −
where, as stated above,
π
P
1
π
P
(3.2.10)
Pi • Qih ,
i=1
βih = 1. Substituting (3.2.10) into (3.2.8) produces an expression for the
i=1
expenditure on commodity i by household category h:
π
X
•
Pi Qih = Pi γih + βih HEh −
Pj γjh .
(3.2.11)
j=1
As expected, the first derivative of equation (3.2.11) with respect to total expenditure HEh is the marginal
budget share, βih . The linear expenditure system (equation 3.2.12) is obtained by dividing equation (3.2.11)
by Pi :
π
X
βih
Qih = γih +
HEh −
(3.2.12)
Pj γjh .
Pi
j=1
To evaluate equation (3.2.12), we need values for γih and βih , prices, and total consumption expenditure data
from the SAM. Because γih cannot be directly estimated from empirical data and because βih cannot be
calculated from a one-period data set in the SAM, equation (3.2.12) is often implemented using a simplified
version of the Stone-Geary LES. Rearranging equation (3.2.12) gives
π
HEh Pi • Qih
βih X
Pj γjh =
− βih .
(3.2.13)
γih −
Pi j=1
Pi
HEh
If we assume that the average budget share is equal to the marginal budget share, equation (3.2.13) implies
the following:
Pi • Qih
βih =
, and
(3.2.14)
HEh
γih −
π
βih X
Pj γjh = 0.
Pi j=1
(3.2.15)
Because 0 < βih < 1 and Pi > 0, the relationship in equation (3.2.15) is guaranteed only if the minimum/subsistence consumption γ = 0 for all commodities. If this is the case, the LES demand function,
equation (3.2.12), simplifies to:
HEh
Qih = βih
.
(3.2.16)
Pi
Coefficients βih are calculated from equation (3.2.14) by using the benchmark data in the SAM. This process
is accomplished by normalizing the prices to one, which transforms the expenditure results in the SAM to
5 Often,
households have been categorized into ’high income’, ’medium income’, and ’low income’. See, for example, Budiyanti.
For simplicity, we assume here that all households are homogeneous (h = 1).
23
physical quantities. In our example (Table 2.1), total household expenditure on both imported and regionally
produced commodities, HEh = $50,665,679,000 and expenditure on agricultural commodities is $328,760,000.
Thus, the marginal (equal to the average) budget share for agriculture is 0.0065. (Click here for a graphic
presentation of the calibrated commodity demand.)
As you notice, equation (3.2.16) is based on very restrictive and somewhat unrealistic assumptions. It
implies that income elasticities of demand are unitary for all commodities. Although the results are not
appropriate for dynamic analysis, this assumption does not pose serious problems for comparative static
analysis, particularly if expenditure patterns for several household income groups are embodied in the model.
For the interested reader, click here for a more general case of the LES demand system, which provides for
leisure, household labor supply, and varying commodity income elasticities.
Commodity substitution of imports for domestic product
The second level of household commodity demand involves determination of the minimum cost combination of
regional and imported commodities. For each commodity i, substitution between the two sources is captured
in the following CES function:
Qih =
φQ
i
1Q
ρ
σiQ − 1
ρQ
ρQ
Q
Q
i
1
∂i QMih + (1 − ∂i )QRih 1 , ρQ
i =
σiQ
(3.2.17)
Q
where φQ
i > 0 is the household consumption efficiency parameter, 0 < ∂i < 1 is the share parameter,
QMih represents household demand for imports, QRih demand for regional products, σiQ is the elasticity
of substitution, and ρQ
i is the substitution parameter. The determination of the domestic (regional) and
imported amounts of a fixed total household demand is the same as presented in equations (3.1.16) to (3.1.19).
(Click here for a graphic presentation of the substitution relationship between imported and regionally produced
commodities as shown in the form of a household indifference curve).
3.2.3
Institutional markets
Governments and capital formation are the two remaining commodity markets represented in the Oklahoma
SAM. Quantity demanded is assumed exogenous for each of these markets. However, price is endogenous
and, hence, expenditure by governments and for capital formation varies with price. Similar to intermediate
commodity inputs and household commodity demands, imported and regionally produced commodities are
imperfect substitutes in meeting the composite commodity demands. Exogenous commodity demand for
governments (QGi ) and capital formation (QCi ) from the two sources (regional and imported) is given by
the following CES function:
QXi =
φδc
i
1
δc
ρ
ρδc
ρδc
i
δc
δc
i
i
∂i QXMi = 1 − ∂i QXRi
ρδc
i =
σiδc − 1
σiδc
(3.2.18)
where QXi = QGi + QCi , QXMi is quantity imported and QXRi is quantity domestically produced. All
parameters are identified similar to those for equation (3.1.16). The elasticities of substitution σiδc are the
same as for intermediate inputs and household demand (see Table 3.1). Solution to quantities imported and
domestically produced is similar to equations (3.1.16) to (3.1.19).
3.2.4
Commodity prices
Composite purchase price
Commodity purchase prices are a composite of regional and import prices:
Pi =
P R i • R i + P Mi • M i
R i + Mi
24
(3.2.19)
The composite purchase price (Pi ) is the unit value for household consumption goods, intermediate inputs,
and institutional purchases. P Ri is the regional purchase price and P Mi is the import price. Ri is the total
amount of commodity regionally produced and consumed and Mi is the total amount of commodity imported:
Ri = T V Ri + T QRi + QXRi
(3.2.20)
Mi = T V Mi + T QMi + QXMi
(3.2.21)
The right hand side terms are as previously defined.
Composite output price
Commodity output prices are a composite of regional and export prices:
P Xi =
P Ri Ri + P Ei + EXPi
Ri + EXPi
(3.2.22)
The composite output price (P Xi ) is the weighted unit value of revenue received from regional and export
sales. P Ri is the regional price and P Ei is the export price.Ri is the regional quantity and EXPi is the
export quantity.
3.2.5
Commodity market equilibrium
Total commodity demand is the sum of intermediate demand, institutional demand, and export demand.
Total commodity supply is the sum of regional production and imports. Market equilibrium for commodity i
is the following:
Xi + Mi = T Vi + T Qi + QXi + EXPi
(3.2.23)
where Xi = regional production, Mi = imports, T Vi = total composite intermediate input demand, T Qi =
total composite household demand, QXi = total composite exogenous commodity demands (governments
plus capital formation), and EXPi = export demand.
3.3
Factor markets and factor incomes
In section 3.1, we derived factor demands for a profit-maximizing firm. However, these industries are not the
only participants on the demand side of the factor markets. Institutions such as governments and households
demand factor services. In addition to discussing institutional demand for factors, this section also describes
the supply side and equilibrium conditions for the factor markets.
In the CGE framework, market behavior for primary factors is studied from both short-run and long run
perspectives. In the short run, capital is assumed to be fixed by sector while labor is assumed to be mobile
between sectors and between regions. In the long run, both capital and labor are mobile between sectors and
regions. Land is assumed fixed in both short- and long run.
Factors are assumed to migrate in search of interregional quantity-price equilibrium. Higher wage rates and
capital rents relative to out-of-region levels encourage in-migration while lower rates induce out-migration.
Few regonal CGE studies have attempted to incorporate interregional mobility in factor markets. In their
national trade model, de Melo and Tarr derived an endogenous labor supply by incorporating leisure as a
commodity in the household utility function. Lee endogenized labor supply by allowing the labor-leisure
choice and labor migration through a labor migration elasticity in his Oklahoma regional CGE model. In
modeling the U.S. economy, Rickman incorporated both labor and capital migration. Budiyanti adapted
Lee’s endogenous household labor supply and incorporated labor and capital migration in a regional CGE
model.
For simplicity in the current exposition, initial institutional endowments and migration are assumed to
influence factor supply. Equilibrium factor prices result when factor demands equal corresponding factor
supplies. Endogenous labor supply (labor-leisure choice) is assumed to be insignificant and, hence, ignored.
In the rest of this section, we present equilibrium conditions for the three primary factors - labor, capital and
25
land - under conditions of no endogenous factor supplies. However, a detailed explanation of the modeling
procedures required to address leisure-augmented household demand systems and endogenous labor supply is
presented in this clickable. Most CGE models assume perfectly competitive factor markets, in which both
firms (factor demanders) and households (factor suppliers) are treated as price takers. In the remainder of
this section, we use the framework of perfect competition to discuss labor, capital and entrepreneurship, and
land as factors and as sources of income.
3.3.1
The labor market
The labor market is in equilibrium when quantity supplied equals quantity demanded. Assuming all labor is
homogeneous, equilibrium is expressed as:2
LSO + LM G = LDI + LDE
where LSO is total initial household labor, LM G is labor migration, LDI =
demand for labor, and LDE is exogenous demand for labor. LDE is equal to:
(3.3.1)
π
P
LABi is total industry
i=1
LDE = LDH + LDG
(3.3.2)
where LDH is labor demanded directly by households and LDG is labor demanded by all government
agencies. The labor row total in the SAM (Table 2.1) shows that LSO = 37,489,772,000 and is equal to
the sum of LDI (30,400,863,000) and LDE (7,088,909,000). This is true when the system is in benchmark
equilibrium because LM G is then equal to zero.
As stated above, labor migration arises due to differences between regional and out-of-region wage rates. The
degree of mobility depends on the labor migration elasticity. This relationship is:
LM G = LSO • δ i • log
PL
P LE
(3.3.3)
where LSO is initial labor supply, P L is regional wage rate, P LE is rest-of-the-world wage rate, and δ i is
labor migration elasticity. δ i is obtained from external sources. For examples in this study, the parameter δ i
is (0.92) and is from Plaut.
Labor income
Total regional labor income (LY ) is the sum of the product of labor demanded and the wage rate:
LY = P L • (Σi LABi + LDH + LDG)
(3.3.4)
where P L is wage rate, LABi is labor demanded by industry i, LDH is labor demanded directly by households,
and LDG is labor demanded by all government agencies. If the labor market is disaggregated by skill type,
total labor income is determined by summing across all skills. Net labor income (N LY ) is determined by
subtracting payroll tax from total (or gross) labor income in equation (3.3.4):
N LY = LY (1 − ss tax)
(3.3.5)
where ss tax is the labor payroll tax rate. All of net labor income (N LY = 31,363,057,000) is distributed to
households (SAM, Table 2.1). Payroll tax rate is ss tax = 0.164.
2 If
labor is differentiated by skill,the relationships presented here would hold for each skill type.
26
3.3.2
The capital market
In the short run, when capital is assumed to be perfectly immobile, the capital market is in equilibrium when
quantity demanded by each industry (CAPi ) is equal to that industry’s initial capital stock (KSOi ):
CAPi = KSOi
(3.3.6)
If capital is mobile (the long run solution), the capital market is in equilibrium when total capital supply,
which is the initial quantity plus migrated capital, equals total capital demand:
KM G +
n
X
KSOi =
n
X
CAPi
(3.3.7)
i=1
i=1
where KM G is capital supply from migration, and KSOi and CAPi are as defined above. Capital mobility
ensures uniform capital rents across industries.
Like labor, capital migration arises due to differences between region and out-of-region rental prices:
KM G =
n
X
KSOi • δ i • log
i=1
PK
P KE
(3.3.8)
where KSOi is industry i’s initial capital supply, P K is regional capital rent, P KE is rest-of-the-world
capital rent, and δ i is capital migration elasticity. The parameter δ i is obtained from external sources. For
examples in this study, the parameter δ i is 0.92 and is taken from Plaut.
Capital income
Total capital income (KY ) is the sum of the product of capital demanded and capital rent:
X
KY =
P Ki • CAPi
i
(3.3.9)
where P Ki is capital rent and CAPi is the quantity of capital demanded by sector i.
In this formulation, capital is fixed with capital rents differentiated by industry. The overall capital rent is:
P
P Ki • CAPi
(3.3.10)
P K = iP
i KSOi
When capital is mobile across sectors and regions, capital income is:
KY = P K • CAPi
(3.3.11)
where P K is the overall capital rent of the region.
Capital is owned by enterprises and households. Enterprise ownership is by corporations. Household
ownership is by self-employed businesses including agriculture. Government subsidies are treated as an
aggregate payment to capital. Thus net capital income (N KY ) is the following:
N KY = (P K − gsub)KY
(3.3.12)
where P K is capital rent and gsub is the government subsidy. From the Oklahoma SAM (Table 2.1), gsub =
0.0494467, EN T K = 12,510,953,000 and HHK = 7,848,069,000. Therefore, N KY = 19,352,336,000 when
P K = 1.0. This is the same as the row and column totals for capital in the SAM.
Other accounting procedures and assumptions could be used in determining net capital income. In particular,
business subsidies could be attributed directly to an industry.
27
3.3.3
The land market
Land is immobile and is assumed perfectly inelastic both in the short- and long run. Thus, the land market
attains equilibrium when land use (LAN Di ) is equal to initial quantity of land T SOi :
LAN Di = T SOi
Total land income (T Y ) is the sum of the product of quantity of land and land rent:
X
TY =
P Ti • LAN Di
i
(3.3.13)
(3.3.14)
where P Ti is gross land rent and LAN Di is the quantity of land demanded by sector i. For the Oklahoma
SAM, agriculture is the only user of land. Net land income (N T Y ) is total land income less land tax:
N T Y = (1 − t tax)(T Y )
(3.3.15)
where t tax is the land tax rate. From the Oklahoma SAM, t tax = 0.0363379 and LAN D = 709,066,000.
Therefore, N T Y = 683,300,000. Because households own all land in the Oklahoma SAM, net land income
accrues to households.
3.3.4
Enterprise income
The source of enterprise income (EN T Y ) is gross capital rents:
EN T Y = P K • EN T K
(3.3.16)
where P K is capital rent and EN T K is the initial stock of enterprise capital.
Claims to enterprise income (EN T Y ) include regional households, governments and a broadly defined capital
account. Governments receive revenues from corporate income taxation. The broadly defined capital account
includes capital depreciation, retained earnings and capital payments to owners of capital (stock) outside
of the region. Because the current regional CGE model is used as an analysis of comparative statics to
marginal changes in the system, enterprise income is distributed to the three entities (regional households,
governments and capital account) as fixed shares. This distribution of income may be realistic for households
and governments but it is unrealistic for depreciation which is generally based on capital stock rather than
capital income.
The assumed distribution is:
HEN T Y = h EN T Y
(3.3.17)
GEN T Y = g EN T Y
(3.3.18)
CEN T Y = c EN T Y
(3.3.19)
where h, g, and c are shares of gross enterprise income distributed to households, governments and capital
account, respectively. These shares are computed from the SAM and are h = 0.1386, g = 0.1359, and c =
0.7255.
3.3.5
Household income
Most household income comes from factor payments. As noted above, gross factor payments are subject to
government taxes and capital depreciation. It is, thus, the total earnings less the applicable deductions that
are available for distribution to owners of factors. Other sources of household income include inter-household
transfers, government transfers, and net remittances from the rest-of-the-world.
Gathering these sources of income for households, gross household income (GHY ) is:
GHY = N LY + P K • HHK + N T Y + HEN T Y + GOV T H + ROW T H
28
(3.3.20)
where N LY is net labor income, P K is capital rent, HHK is capital stock owned by households, N T Y is net
land income, HEN T Y is household enterprise income, GOV T H is government transfers to households, and
ROW T H is net transfers and remittances to households from rest-of-world. The latter two sources do not
depend on regional resource ownership and factor prices. These sources are exogenous and assumed constant
for the following analyses. All values may be read directly from the household row in the SAM.
Disposable household income (DHY ) is:
DHY = (1 − hh tax) • GHY
(3.3.21)
where ht is the household income tax rate. For the Oklahoma SAM, hh tax = 0.1294835.
Household savings (HSAV ) is:
HSAV = mps • GHY )
(3.3.22)
where mps is the savings rate. Because this is negative in the Oklahoma SAM for 1993, it implies a negative
savings rate for the aggregate of households. It is not uncommon for households to expend more than their
income, particularly lower income households where inter-household transfers are large and expenditures
are based on expected future earnings. In the Oklahoma SAM, because there is one household group,
inter-household transfers are netted out of gross household income. In this case, mps = -0.0718137.
Because the model allows for labor and capital mobility, adjustments need to be made in factor compensations
to households to assure that ownership of resources by households does not change with resource mobility.
This is a major difference between regional and national CGE modeling. National models need not account
for mobility of resources within the national boundary to hold original resource ownership constant by
household group. For regions, households own labor, capital and land and receive transfers (inter-household,
governments and rest-of-world). If labor moves, it is generally the household that relocates with its ownership
rights to not only labor but also to capital and land. If resource adjustments are not made with labor mobility,
changes in regional gross household income accounting may be the result of unintended changes in household
resource ownership.
Consider household labor income with migration. Equation (3.3.1) shows regional labor market equilibrium
with migration. Migration is shown in equation (3.3.3). Labor income (LY ) for the benchmark (initial)
regional households is the following:3
LY = P L(LDI + LDE)
√
2
LM G − LM G 0.5
+ P LE
√
2
− PL
LM G + LM G 0.5
(3.3.23)
where all terms are as defined before. The first term on the right hand is regional gross labor compensation.
The second term identifies out-migration and the compensation received when outmigrating. The third term
identifies in-migration and the compensation received by immigrants. In-migration and out-migration are
mutually exclusive as shown in the migration equation (3.3.3). Click here for two hypothetical examples of
equation (3.3.23).
Household income from capital depends on household capital ownership and capital rents. Under the
assumption of no capital mobility (short run with capital fixed by sector and region, i.e. equation 3.3.6), the
initial regional households own capital resources equal to HHK = 7,848,069,000 and are compensated equal
to P K • HHK where P K is the average regional price of capital.
Even though capital is immobile, with labor migration, households migrating out are assumed to take with
them their proportion of capital rents which are further assumed to be spent out of the region. Those
3 This
formulationappears in the Amera and Schreiner regional CGE.
29
households remaining in the region will receive their proportionate share of capital compensation. Labor
(household) in-migration is assumed to bring no other resource (capital and land) rents into the region. This
assumption may be modified if further information is available.
Capital compensation to households is equal to:
Y KH = P K • HHK
The proportion of initial households associated with labor out-migration is:
√
( LM G2 − LM G)0.5
aLM G =
LSO
(3.3.24)
(3.3.25)
where aLM G is used to show an adjustment amount to the following income variables. Only when LM G
is negative (i.e. out-migration) will the numerator be greater than zero. When LM G is positive (i.e.
in-migration) aLM G will be zero. The capital compensation to households remaining in region is:
RY KY = (1 − aLM G)Y KH
(3.3.26)
If aLM G = 0 , then all of Y KH remains in region.
With capital mobile, capital resources owned by the initial households are used in-region or out-of-region
depending on the proportion of capital out-migration to initial capital stock. The proportion of capital
migration to capital stock is:
√
( KM G2 − KM G)0.5
P
aKM G =
(3.3.27)
KSOi
1
The assumption is that the same proportion of out-migration of capital applies equally to households and
enterprises.
Capital compensation to households remaining in-region and with capital mobility is:
RY KH = (1 − aLM G)(1 − aKM G)Y KH
+ P KE • aLM G • HHK
(3.3.28)
The first term on the right adjusts capital compensation to households (Y KH) for out-migration of labor
(1 − aLM G) and out-migration of capital (1 − aKM G). The second term adds back in the compensation for
out-migration of capital but at a higher capital rent because P KE > P K.
Compensation for capital in-migration adds to gross regional (state) product but is assumed to flow back
out-of-state because ownership resides out-of-state.
Household income from land depends on land ownership and land rents. All net land income (equation 3.3.15)
accrues to households:
N T Y H = (1 − t tax)T Y
(3.3.29)
However, with labor out-migration, a proportion of N T Y H flows out of state. The proportion of N T Y H
remaining in-state is:
RN T Y H = (1 − aLM G)N T Y H
(3.3.30)
where the argument is the same as for capital income given in equation(3.3.26).
Enterprise income, government transfers and rest-of-world remittances accruing to the initial regional
households (equation 3.3.20) remaining in-region under conditions of labor out-migration is given as:
REY H = (1 − aLM G)(HEN T Y + GOV T H + ROW T H)
(3.3.31)
Benchmark data is in equilibrium with labor and capital migration equal to zero. However, changes in
equilibriums under comparative statics should allow for mobility of labor (households) and capital. As a
result, three possible household groups are identified, with their own sources of income and their own effects
on regional variables including commodity demands, savings and taxation. Each household group is presented
by a set of income accounting equations.
30
Regional households
This group of households is part of the initial set of regional households and remains in the region after
resource mobility occurs and a new equilibrium is attained under comparative statics. It is this group that
is of primary interest in measuring welfare change from a change in regional policy or regional structure.
Income to regional households includes net labor income, gross capital income, net land income, enterprise
income, government transfers and rest-of-world net remittances:
√
RHHY = [LY (1 − ss tax) − P LE( LM G2 − LM G)0.5]
+ RY KH + RN T Y H
+ REY H
(3.3.32)
The first term is household labor income adjusted for payroll taxes (equation 3.3.5) and labor out-migration
(equation 3.3.23); the second term is household capital income adjusted for capital rents following labor
migration (equation 3.3.26); the third term is net land income adjusted for land rents following labor migration
(equation 3.3.29); and the fourth term is household enterprise income, government transfers and rest-of-world
remittances, all adjusted for labor out-migration (equation 3.3.31). Under the conditions of capital mobility
in addition to labor mobility, (equation 3.3.26) is replaced by (equation 3.3.28) and this becomes the second
term in (equation 3.3.32).
Regional household expenditure for commodity demand is equal to:
RHE = (1 − hh tax-mps) ∗ RHHY P L ∗ (1 − aLM G)LDH
(3.3.33)
where hh tax = household income tax rate, mps = household savings rate, and P L • (1 − aLM G)LDH is
household payments directly to labor adjusted for out-migration. The latter is included because payments
directly to labor are not part of the household demand (expenditure) system.
Labor out-migration households
Households associated with labor out-migration take with them the value of their labor plus their capital
and land rents from the initial distribution of resource ownership. Similarly, the region has less government
transfers and less rest-of-world remittances. These reductions translate into less expenditure in the region
and less government tax revenue and regional savings.
Income of out-migration households is the following:
√
OM HHY = P LE( LM G2 − LM G)0.5
+ aKN G • Y KH + aLM G • RN T Y H
+ aLM G • H • EN T Y
(3.3.34)
where the first term is the labor compensation received out of the region. Notice that payroll tax is not
included because this tax would be paid in the region of employment. The second term is capital rents and
the third term is net land rents associated with regional resource ownership of migrating households. Notice
that capital subsidies flow out but that land tax remains within the region. The fourth term is enterprise
income associated with out-migrating households. Because this income is from capital ownership, it is treated
the same way as direct capital payments to households.
Although regions lose government income tax revenue on labor income, regions keep income tax revenue
(OM GR) on capital and land rents and enterprise income:
OM GR = hh tax • aLM G(Y KH + RN T Y H + H • EN T Y )
31
(3.3.35)
Labor in-migration households
Income associated with labor in-migration households is assumed limited to only their labor compensation:
√
IM HHY = P L( LM G2 + LM G)0.5
(3.3.36)
Regional expenditure associated with this income is equal to:
IM RE = (1 − hh tax-mps)IM HHY
(3.3.37)
It is this expenditure which accounts for the commodity demands of in-migrants in their linear expenditure
system.
3.4
Measures of regional and household welfare
The primary purpose of CGE analysis is to evaluate policy and policy change. Policymakers frequently
evaluate policy change using several criteria. Two broad criteria are presented here with each subdivided into
more specific welfare measures. The first broad criteria is regional welfare and emphasizes policy change on
regional macro-variables. Because of the openness of regions, these measures are prone to emphasize place
prosperity (or growth) with little insight on how policy changes welfare of people. The second broad criteria
is household welfare and emphasizes people prosperity irregardless of where people eventually reside. This
criteria considers both income effects and price effects in evaluating welfare of households residing in the
region.
3.4.1
Regional welfare
Gross regional product
The most comprehensive measure of regional change is gross regional product (GRP ) or, if for a state,
gross state product (GSP ). This measure accounts for the quantity of primary factor inputs used and the
compensation to each input. It generally includes the indirect business tax paid by industry. It includes total
compensation for labor by industry including payroll taxes and employee benefits. It includes gross returns
to capital (including profits) before depreciation.
GRP are payments to resources used (or employed) in the region irrespective of where resource owners reside.
Thus, factor payments flow to resource owners located within the region and outside the region. It is not
necessarily a good measure of welfare change of households residing within the region.
For Oklahoma, GSP is the sum of all factor payments ($57,551,174,000) plus indirect business tax
($5,268,195,000) for a total of ($62,819,369,000). The following variables account for GSP :
XX
GSP = LY + KY + T Y +
ibti P Ri Xi
(3.4.1)
i
where the right hand terms are, respectively, gross labor income, gross capital income, gross land income, and
indirect business tax. The following is the index of change in GSP :
IGSP = (GSP − GSP O)/GSP O
(3.4.2)
where GSP O is the benchmark value of GSP .
Regional expenditure
Regional expenditures are defined here as aggregate expenditures by households, governments for consumption
and businesses for capital formation. If regional expenditures are expanding, one would expect the state’s
economy to be growing. Expenditures as defined here are not adjusted for regional commodity imports.
Presumably, households and governments have increasing incomes and revenues to support increasing
expenditures, and investment opportunities are available to support increased capital formation.
32
Several caveats prevent this regional welfare measure from portraying viable economic growth. First, increased
expenditure may be the result of increased commodity prices. A separate regional welfare measure accounts
for the overall increase in price level. Second, expenditures may be financed from short term dissavings,
government transfers, or out-of-region remittances. The negative savings ratio by households for Oklahoma in
1993 implies a dissavings for purposes of current consumption. Third, because governments were combined in
the Oklahoma SAM, we can not view expenditure of only state and local governments. Federal government
expenditures are more appropriately classified with regional exports. Fourth, double counting occurs because
of government ransfers to households and household tax payments to governments. Fifth, for the current
CGE model, government expenditures and capital formation are exogenous and change only as commodity
prices change. Of course, other behavioral conditions can be modeled for describing these expenditures.
The following variables account for regional expenditures:
X
Pi (QXi )
RE = HE +
(3.4.3)
i
where the right hand terms are total regional household expenditures and total exogenous commodity demand
expenditures. The following is the index of change in RE:
IRE = (RE − REO)/REO
(3.4.4)
where REO is the benchmark regional expenditure.
Regional price level
Composite commodity prices are endogenous to the regional CGE. Therefore, growth in the monetary variables
for the region may be because of quantity changes and/or price changes. Export and import commodity
prices are exogenous but the composite price is endogenous because it is a weighted average of the domestic
regional and import prices. The overall regional price level may be calculated as either a weighted index of
the composite commodity prices or of regional output prices. The former is useful in measuring the effects of
prices on regional expenditures. The latter is useful for comparing the overall regional price level to external
price levels.
The price index presented here weights the price changes by the benchmark quantities. Other price indexes
may be used to measure changes in the overall price level.
The composite commodity price level is the following:
P
P
P Ri • ROi + P Mi · M Oi
i
P
P = i
(ROi • M Oi )
(3.4.5)
i
where ROi and M Oi are benchmark quantities of regional market supply and imports, respectively. The
price level index relative to the benchmark price level (i.e. P O = 1.0) is the following
IP = 1 +
P − PO
= P/P O
PO
The regional output price level is the following:
P
P
P Ri • ROi + P Ei • EXP Oi
P i
PX = i
XOi
(3.4.6)
(3.4.7)
i
where XOi is benchmark quantities of regional output. Presumably, with an increase in P X, regional output
would be expanding and regional growth would occur. Similarly, with a P X less than one, regional output is
decreasing and regional growth is contracting. The effects of this price level is particularly important when
evaluating productivity changes in a region.
33
Net government revenue
Another important regional welfare measure is the change in net government revenue. An important policy
question is whether a regional change in structure or policy adds more to regional government costs than
is received in regional government revenue. This welfare measure is not considered here because of the
aggregation of all government units (including federal) in the SAM. Several CGE studies are available
that have disaggregated the governmental jurisdictions to trace government expenditures and revenues in
considerable detail. One of the most detailed is a California study by Berck, et al. It also contains a review
of the current literature in this area of application of CGE modeling.
Other regional measures of welfare
The rest-of-the world current trade account compares a region’s exports to its imports. The importance of the
balance of trade account is not so much that the aggregate of exports exceeds the aggregate value of imports
as that the sources of exports and imports are identified. This assists in evaluation of the regional terms of
trade, a comparison of the aggregate export price with the aggregate import price. Frequently, a region has a
more limited array of export commodities compared to its basket of import commodities. This may lead to
highly volatile terms of trade for some (especially small) regions. More diversified regions have less volatile
terms of trade. Regions that have large export values compared to import values will have counter balancing
monetary flows in the financial markets. Agriculturally related regions and older matured regions frequently
have large monetary flows out of the region to counteract revenue inflows from exports. This generally means
these regions have fewer investment opportunities compared to other regions. These results may be captured
by constructing a balance of payments account for regions.
3.4.2
Household welfare
Household income
The most widely used measure of household welfare is household income. This measure is available in
government documents for states and regions by time periods. However, to reproduce this measure from
a CGE analysis after simulating a policy or impact change is not straight forward. In the regional CGE
framework, households have an initial resource ownership with initial unit values. In addition, they have
other sources of income such as government transfers and transfers from other households. In the typical
comparative static analysis of policy or impact change, resource ownership and transfer income are held
constant by household with emphasis on changes in unit values of resources and regional mobility of resources
(labor and capital). The result is an accounting of income for three household groups after the policy change:
(1) initial (benchmark) households remaining in the region, (2) initial households that migrate form the
region, and (3) households added to the region through in-migration. Incomes for these three household
groups are given in the equations of section 3.3.5.
Household incomes generated from regional CGE models are in nominal terms. To express in real terms,
regional household incomes should be adjusted for changes in regional price level. One price index that
may be used is the composite commodity price level calculated from equation (3.4.6). This adjusts regional
household incomes by the purchasing value of commodities in the region.
Compensating and equivalent variation
Utility measures for individuals and households are the result of preferences expressed through markets.
Similar measures are not available for regions. Policymakers express preferences for regions. Regional
policymakers frequently choose preferences (goals) such as maximizing regional employment growth or
maximizing gross regional product (GRP) or income. Such goals have little relevance when how they affect
the welfare of individual households or groups of household is unknown (Levin). Maximizing employment
growth may lead to trading many low paying jobs for fewer high paying jobs. Maximizing GRP may lead
to emphasizing a regional structure of large corporate ownership of resources with high regional outflows
of factor payments versus a regional structure of local ownership of resources with low regional outflows of
factor payments.
34
An alternative goal is to increase welfare of one or more household groups within the region. Moving from
one market result to another market result presumes a welfare change for most, if not all, household groups.
To measure this change from a policy or program change, welfare must be measurable. Because utility is
not directly measurable, an alternative measure must be chosen. An observable alternative for measuring
the intensities of preferences of an individual for one situation versus another is the amount of money the
individual is willing to pay or accept to move from one situation to another (Just, Hueth, and Schmitz, p.
10). The two most widely accepted willingness-to-pay measures are compensating and equivalent variations
first proposed by Hicks. Compensating variation (CV) is the amount of money which, when taken away from
an individual after an economic change, leaves the person just as well off as before. Equivalent variation (EV)
is the amount of money which, if an economic change does not happen, leaves the individual just as well off
as if the change had occurred (Just, Hueth, and Schmitz, pp. 10-11). Which welfare measure is employed
depends on whether initial prices or new prices are used. The CV measure is based on new prices, and the
EV measure is based on initial prices. Information on the distribution of welfare gains and losses among
household groups should be useful to policymakers in making judgments on whether this policy result is
inferior or superior to an alternative policy result.
Application of these criteria in national CGE models is available in de Melo and Tarr. Application to regional
CGE models for Oklahoma are in studies by Lee, Budiyanti, and Amera. The equational forms for CV and
EV are presented in Table 4.1.
35
4
Model Execution
In this section the procedure for implementing the regional CGE is presented as discussed in section 3.0.
Because section 3.0 explains and derives the equations for a competitive regional CGE, there are more
equations than needed for actual model execution. Section 4.1 puts in tabular form the actual model
equations needed for execution (Table 4.1). Also, subscript notation is in Table 4.2; summary of endogenous
variables is in Table 4.3; summary of exogenous variables is in Table 4.4; and summary of parameters is in
Table 4.5.
A brief discussion of the General Algebraic Modeling System (GAMS) solution is presented in section 4.2 with
reference to more detailed procedures. The actual model construction in GAMS is presented in section 4.3.
The model itself can be downloaded for purposes of experimenting with model changes and model simulation.
(Click here to download GAMS input file).
Results of a simulation of increased terms of trade for the region is presented in section 4.4.
4.1
Competitive CGE model equations
Table 4.1 Competitive CGE Model Equations
Table 4.2 Subscript Notation
Table 4.3 Summary of Endogenous Variables
Table 4.4 Summary of Exogenous Variables
Table 4.5 Summary of Parameters
4.2
GAMS Solution
A CGE Model is an integrated system of equations whose simultaneous solution determines values of
endogenous variables. The underlying equations are derived from economic theory of the behavior of
economicagents and markets – producers, institutions, factor markets, etc. Several approaches have been
used to solve these models. Dervis, de Mello and Robinson have classified these algorithms into fixed point
theorem based, tatonment process based and Jacobian approaches. Most recent CGE applications have used
General Algebraic Modeling System (GAMS) whose solvers fall in the third category.
GAMS is a high-level modeling system consisting of a language compiler and a stable of integrated highperformance solvers. It is specifically designed for modeling linear, nonlinear and mixed integer optimization
problems and is tailored for complex, large scale modeling applications. This permits building of large
maintainable models that can be adapted quickly to new situations. One of the advantages of GAMS is that
it is designed to accept equations in almost the same format as presented in Table 4.1. The use of subset
notation allows implementation of different functional forms and closure rules for different subsets (in a
variable vector) without having to introduce dummy variables. By eliminating the need to think about purely
technical machine-specific problems such as address calculations, storage assignments, subroutine linkages,
and input-output and flow control, GAMS increases the time available for conceptualizing and running the
model, and analyzing the results. Detailed programming procedures are provided in Brooke, Kendrick and
Meeraus.
Because of the presence of nonlinear functions in CGE model formulations, finding solutions requires use of
nonlinear algorithms. Several such solution algorithms are present in GAMS. The syntax of optimization
characteristic of GAMS requires an objective function with the rest of the CGE equations treated as constraints.
Because none of the equations has an inequality sign in CGE, the model solution is invariant to choice of
objective function. Therefore, any equation is eligible to be an objective function, as long as it is a scalar
equation.
For empirical implementation, (two) positive slack variables are introduced in one of the equations (in our
case, the production function). To equate the number of endogenous variables to the number of equations
and, hence, to ensure full identification of the system, an extra equation is introduced which sums up the
36
two slack variables. In the optimization process, the sum of the slack variables is minimized subject to all
other equations (equality constraints). This ensures that the optimal solution is attained when the sum
of the slack variables is equal to zero, a condition necessary to satisfy all the simultaneous equations in
the model. With benchmark exogenous variable values, the program will replicate exactly the values of
the endogenous variables contained in the SAM at the optimum. Thus, the introduction of slacks only
facilitates the optimization process and does not affect the solution values. Brooke, Kendrick and Meeraus
also recommend this (slack variable) technique in nonlinear optimization, arguing that it helps to address the
infeasibility problem that frequently occurs during iterations in such models.
4.3
Model construction in GAMS
The model construction is presented in the syntax of the GAMS software program. For a guide to the
GAMS-input-file click in this link user’s guide to GAMS-input-file. To execute a GAMS program the reader
must have the GAMS software program. For more information on how to obtain, install and run the GAMS
software see this link {http://www.gams.com/}.
4.4
Model simulation
A change in regional terms of trade is used to show the results of a model simulation. Export prices for all
commodities were increased five percent with import prices remaining at base level. This is similar (but in
the opposite direction) to the impact of a decrease in agricultural commodity export prices during the mid
1980s, which contributed to considerable stress and change in rural Oklahoma. An overall price index in
1982 of 100 for agricultural commodities produced in the state was 89.0 by 1986 (Schreiner, Lee, Koh and
Budiyanti, p 64). This implied about an 11 percent decrease in export prices of agricultural commodities
during a relatively short period of time.
Simulation results of a five percent increase in terms of trade (5 % increase in all export prices), assuming
long-term adjustment and capital mobility, are presented in Table 4.6 (below). These results are based
on a recent paper by Tembo, Vargas and Schreiner presented at the 30th Mid-Continent Regional Science
Association meetings, Minneapolis, MN, June 11-12, 1999.
Table 4.6 Effects of a 5% Change (Plus) in Terms of Trade,
Oklahoma, 1993
Welfare index
Variable symbol Base value Simulation result
Total exports
EXP
1.0000
1.1375
Total imports
M
1.0000
1.0887
Composite price
P
1.0000
1.0161
Household income
RHHY
1.0000
1.0814
Gross state product GSP
1.0000
1.1032
Total exports increase by 13.8% and imports increase by 8.9%. Remember that exports and imports are
constrained by constant elasticities of transformation (CET) and constant elasticities of substitution (CES),
respectively. This means that producers respond not only to a change in the price ratio of export markets to
domestic markets but also to their willingness to substitute (transform their product) between the markets.
Consumers in the regional (domestic) market must also adjust to higher regional prices (not shown for
individual commodities in Table 4.6). On the import side, consumers are faced with higher regional prices and
thus substitute imports (which are at the same price as before the simulation because they are exogenously
set) for regional products, based on their willingness to substitute (i.e. the CES parameter). The small region
effect is assumed here where regional output and regional demand do not change external prices.
The index of the composite price, a weighted average of regional and import prices, increases by 1.6%. This is
the price regional (state) consumers pay for purchases within the region (state). Regional consumers include
households, intermediate input buyers and governments. Incomes of regional households increase by 8.1% in
nominal terms. By deflating nominal income by the composite price index, real income increases by 5.06%.
Gross state product (GSP) increases by 10.3%. GSP is the compensation for all resources employed in the
state, no matter whether the resource owners reside in-state or out-of-state. GSP is the result of the changes
37
in resource prices (wages and rents) and quantity of resources employed. In this simulation, wages and rents
increase (not shown in Table 4.6) and quantities of labor and capital increase through migration. The latter
increase because resource prices in the state are higher relative to prices out-of-state. Again, the small region
effect is assumed where the regional demand for resources does not stimulate price increases out-of-state.
Results similar to Table 4.6 could be calculated to show the change in all endogenous variables (see Table
4.3). Because CGE emphasizes relative changes, results are generally expressed by index form showing the
percent change from the base. Hence, an index of 1.1032 for GSP indicates a 10.32% increase over the base,
whereas an index of 0.9600 would indicate a 4% decrease in GSP. Absolute changes are easily calculated by
applying the percent change to the base level. For example the 10.32% change in GSP applied to the factor
payments, $57,551,174,000, in Table 2.1 results in a change in GSP of $5,939,281,157 (excluding indirect
business taxes paid to governments).
5
Increasing Returns and Imperfect Competition in Regional
CGE Modeling
The CGE framework presented so far expands beyond the assumptions of input-output (I-O) based models.
By relaxing the assumption of fixed prices, which in I-O models implies that increased demand is always met
with no price increase due to excess production capacity and limitless supply of labor and other factors, we
have a more realistic empirical model of regional analysis. The CGE framework allows demand and supply of
commodities and resources to depend on prices. Furthermore, resources may be substitutable in production.
However, the competitive regional CGE modeling presented above has two important limitations. First, it
does not consider the presence of imperfect competitive market structure and, second, it ignores production
technologies characterized by increasing returns to scale (IRS). We present here regional CGE modeling of
increasing returns to scale and imperfect competition. An introduction to the theoretical difficulties brought
about by the inclusion of returns to scale to the competitive CGE framework is presented. The purpose is to
introduce the reader to limitations of the modeling techniques presented above. But first, the case of forest
product production and wood processing in Oklahoma is used to show the potential for increasing returns to
scale and imperfect competition.
The wood-products manufacturing sector in Oklahoma has several highly concentrated industries. For example,
in the sawmills and planning mills industry (SIC 242) 70% of total employees work for one multinational
company. Similarly, the paper mills (SIC 262) and the paperboard mills (SIC 263) industries are represented
by seven establishments of which 82.5% of total labor force works for two multinational companies. In
addition to the high concentration of the industry, Oklahoma timber producers have limited options on where
to sell their timber because of costly transportation and long distances between processing centers. All of this
propitiates some kind of imperfect structure for the timber market (raw materials market) in which wood
processing industries are capable of affecting the price paid for timber.
Once the price taking assumption is dropped, we face the challenges of modeling changes in the economic
environment, government policies, technological advances, and external shocks. Researches have available to
them considerable theoretical ground on how to model imperfect competition. Two approaches are partial
equilibrium and general equilibrium. They differ in that the former considers regional wages and income
of consumers to be determined outside of the model. As researchers in economics try to maximize their
contributions to solving economic problems they are also constrained by time and data availability. CGE is
more demanding on both time and data. Therefore, it is important for the profession to understand and
contrast the benefits of using one approach over the other. Thus, using the Oklahoma’s forest products industry
(FPI) we contrast empirically the strengths of partial and general equilibrium approaches when modeling
imperfect competition. We estimate the effects on household welfare, gross state product, employment,
raw material prices, wage rate, returns to capital, and so on, for different imperfect market structures of
Oklahoma’s FPI.
38
5.1
Increasing returns, non-convexity, and competitive CGE models
The existence of increasing returns to scale (IRS) relies on the non-convexity of the production set. Nonconvexity undermines the assumptions used to prove existence of general equilibrium. For the standard
competitive general equilibrium, the equalization of prices and marginal rates of transformation is a necessary,
and under the assumption of convex preferences and choice sets, a sufficient condition for optimality. This is
not the case when non-convexity is present. To understand why, we may use the following line of thought.
The presence of IRS leads to large-scale firms because at some price ρ0 above minimum average cost, profits
increase indefinitely with the scale of operation. This is a direct result of average cost always being greater
than marginal cost under IRS. Thus, as firms increase the scale of operation the market becomes more and
more concentrated which in turn leads to fewer and fewer firms (even one) in the industry and possible
collusion of prices. Theoretically, the price mechanism loses its efficiency characteristics and the optimality
and efficiency dichotomy that attracts us to competitive general equilibrium (Villar). Indeed, firms with IRS
are not consistent with the hypothesis of perfect competitive markets.
The presence of IRS is not the only case that precludes the benefits of competitive equilibrium. Imperfect
competition, for example, may be a direct consequence of limitations to entering the market or of a firm’s
exclusive right to use a resource granted by the regional, federal, or local government. We concentrate
in modeling increasing returns and imperfect competition while motivating the reader to investigate the
extensions of our modeling description.1
5.2
Modeling increasing returns and imperfect competition
Harris’ work is considered by many as the first successful and compelling general equilibrium model to
incorporate both imperfect competition and increasing returns to scale. His work deals with a small open
economy and formulates for the first time the modeling of IRS using the dual approach (see below). After
Harris’s work, imperfect competitive general equilibrium models have been extensively used, especially in
trade liberalization issues.
Imperfect market structures that characterize the product side of the production system have been the
major focus of the majority of theoretical and empirical work. Monopolistic competition and oligopolistic
competition, for example, have extensively been applied in trade models. However, market imperfections
related to the factor (input) side of the production system remain unexplored. The reason, at least in the
opinion of these authors, is the international trade focus of most national CGE models where factor market
imperfections are of less concern: i.e., how strong is the case for monopsony modeling when commodities are
traded nationally and internationally?
However, at the regional level and particularly for agriculture and other natural resource based sectors, one
may argue for modeling input side market distortions , i.e. monopsony and cooperative behavior (see Rogers
and Sexton). Thus, the state of the art of CGE is very promising for output distortions of markets but less
promising for distortions of input markets.
5.2.1
Increasing returns -- the dual approach
The modeling of IRS at regional levels is adopted from literature on international trade and national CGE
formulations. Its implementation/adaptation to regional CGE models has been limited with few exceptions
identified by Partridge and Rickman. Harris’ basic approach is used here. The main characteristic of the
approach is the use of the dual formulation of increasing returns to scale. Duality is less restrictive in modeling
and allows treatment of the assumption of convex input requirement sets as compared to the primal approach.
Under constant returns to scale, marginal costs are assumed to be constant and equal to average variable
cost(V Ci /Xi , where V Ci is variable costs and Xi is output for the ith sector). Under increasing returns to
1 Several issues are still not totally clear on theoretical grounds. First, the selection of the numeraire has no implication for
the competitive CGE framework; however, this issue is still controversial when imperfect competition is involved (see, Ginsburgh).
Furthermore, the possibility of non-uniqueness of equilibrium is “a potentially serious problem” for applied general equilibrium
models with imperfect competition and economies of scale (Mercenier). Finally, regional CGE modeling has adapted concepts
and specifications from the national and/or trade CGE literature; however, the implications of its implementation at the regional
level has been greatly criticized (i.e., the Armington assumption on product differentiation).
39
scale, average cost is a monotonically decreasing function2 .
AC =
FC
+ MC
X
(5.1)
where F C is fixed costs and M C and AC are marginal and average cost, respectively. We assume that
marginal costs are governed by the preferred constant returns to scale production function, but a subset of
inputs are committed a priori to production and these costs must be covered regardless of the output level.
Thus, increasing returns to scale takes the form of unrealized economies of scale in production. There is no
customary procedure in defining fixed costs. Fixed costs may involve the same mix of inputs as marginal costs
or, alternatively, fixed costs may be assumed to involve a different set of inputs. However, the specification of
the fixed costs has important consequences for the calibration procedure (to be discussed).
As a measure of unrealized scale economies it is customary to use the concept of cost disadvantage ratio
(CDR). The CDR provides an estimate of unrealized economies of scale (de Melo and Tarr). Depending on
the value of this ratio, an industry may be facing economies/diseconomies of scale or it may be operating at
the minimum efficient scale. The CDR is calculated as:
CDR = 1 −
1
S
(5.2)
where
AC
MC
and AC and M C are average cost and marginal cost, respectively. Thus, If CDR > 0, there are Economies of
Scale; if CDR < 0, there are Diseconomies of Scale; and if CDR = 0, the firm is operating at the Minimum
Efficient Scale 3 .
S=
5.2.2
Increasing returns -- the primal approach
The primal approach in modeling increasing returns to scale has been infrequently used by CGE modelers.
The reason is the indeterminacy under increasing returns to scale. Kilkenny, however, argues that “when
factor markets are geographically segmented and the pool of labor is limited” factor costs will rise for an
industry which is expanding operation using unexploited increasing returns to scale. Thus, existence of an
optimal output level is thus obtained.
In the primal approach, increasing returns to scale are much easier to model. We adjust, for example,
the
P
αf > 1
coefficients of a Cobb-Douglas production function to exhibit increasing returns to scale: making
f
where f states for factor index and α is the exponential (share) parameters in the Cobb-Douglas technology
specification.
5.2.3
Market power
Before modeling market power we require specification of the degree of product differentiation used in the
model. We assume Armington preferences at the regional level. Thus, substitution in purchases is allowed
between domestically produced consumer goods and out-of-region produced consumer goods. Traded goods
are imperfect substitutes by origin and goods produced domestically are imperfect substitutes for imports.
Also, goods supplied on the domestic regional market are imperfect substitutes for goods supplied for export.
Armington specifications also apply to sectors with IRS. In those sectors, goods are produced by Nt identical
firms implying goods produced for domestic sales in these sectors are perfect substitutes.
2 An alternative specification states average cost as AC = X φ−1 f (ω) where f (ω) represents the cost function for a homogenous
bundle of primary and intermediate inputs. This alternative formulation is used to specify scale economies due to returns from
specialization.
C(Y )
3 For multi-product scale economies we carry out the following modification: S =
where C and Yi are, respectively,
ΣY dC/dY
i•
cost and output of the it h product.
40
i
Contestable pricing
Two pricing hypotheses are considered for the IRS sectors. First, we assume low-cost entry and exit such
that the threat of entry forces firms to price at average cost. This is called the contestable pricing behavior:
P X = AC
(5.3)
where P X is the weighted sum of the unit sales prices on the regional (P R) and export (P E) markets. Firms
in a perfectly contestable market will be forced to operate as efficiently as possible, and to charge as low a
price as long-run financial survival permits.
This pricing rule represents only a small departure from the competitive pricing rule because price also equals
average cost in the long-run equilibrium of the competitive model (de Melo and Tarr). Another advantage of
contestable pricing is that it is easy to calibrate. According to de Melo and Tarr, the calibration process is
complete by just equating output price to average cost.
From monopoly to oligopoly
In the second alternative, we assume that each (identical) firm behaves in the regional market as if it is facing
a downward-sloping demand curve. The equilibrium condition for each firm is given by:
1+θ
PR − MC
=
PR
N •δ
(5.4)
where δ is the endogenous elasticity of aggregate sectoral demand, N is the number of firms, and θ is the
representative firm’s conjecture about the response of competitors to its output decision. This alternative is
the conjectural variation specification where one may or may not have entry/exit assumptions.
In long-run equilibrium, entry/exit ensures zero profits. If N represents the number of firms, then as N → ∞
we expect θ → 0; thus, firms behave competitively. Why should the representative firm’s conjecture banish as
the number of firms increase? Two explanations are given. First, collusion is difficult if more firms arrive to
the market, and second, more firms imply greater availability of varieties. A conjectures formulation that
accounts for both product variety and effects on collusion of firms is given by:
θ=
∆Q−1
= N −1
∆Q1
(5.5)
where ∆Q−1 is the change in aggregate output of other firms due to a change in the j th firm, and N is an
arbitrary number normalized to unity in the calibration.
On the other hand, with barriers to entry it is possible to have supernormal profit because firms sell in the
domestic regional market at a price P̃ R > P R. If we define an exogenous rate of profit (Ψ) per unit of
regional sales, then the mark-up pricing equation (5.3) is replaced by:
P X • (P̃ R, P E) = AC • (1 + Ψ)
(5.6)
This equation is the same for contestable market scenario when Ψ = 0. In the conjectural variation case, we
have π = Ψ.
Our empirical example applies all of these modeling techniques to the Oklahoma region. For example, high
concentration in the pulp manufacturing industry increases the likelihood of lower outputs and higher price
than under a competitive structure. As well, its actions may distort the timber market, thus affecting the
welfare of both forest land owners and consumers (Tillman).
5.3
5.3 Calibration
We calibrate our model using a modified social accounting matrix that identifies the forest complex. We
have considered the forest complex to constitute the forestry sector and the forest product industry (FPI).
41
Our calibration procedure depends on assumptions of market structure and strategic behavior by firms.
Calibrating parameters of the model utilizes the information obtained from econometric work and/or economic
theory.
Depending on the price rule and the exit/entry assumption, each alternative entails a different model
calibration. In the case of normal initial profits (Ψ = 0), we reduce the primary variable cost component of
total costs by the amount of fixed costs. For the monopolistic case, equation (5.4) is solved to yield the value
of the conjecture θ parameter.
In the case of supernormal profits, we allocate fixed costs as before. Then, given the profit rate, Ψ, and all
quantities and out-of-region prices, we solve for the region (domestic) price P̃ R which satisfies the firm’s
profitability constraint. Finally, θ is solved from (5.4) but with the new set of regional prices.
Modeling IRS and imperfect competition requires additional parameters, mainly estimates of the following
elasticities: elasticity of capital/labor substitution; import price elasticities of demand; and export supply
price elasticities. Finally, the calibrated price elasticity of demand, ε, will depend on the functional form
selected to represent import demand and export supply.
An example of the application of CGE to imperfect markets in the forest product industry is available in
a paper presented by Vargas and Schreiner at the Mid-Continent Regional Science Association meetings,
Minneapolis, MN, June 11-12, 1999 and published in The Journal of Regional Analysis and Policy (Vol. 29,2:
51-74, 1999)(see website http://www.jrap-journal.org/pastvolumes/1990/v29/29-2-3.pdf).
42
6
Policy Applications and Summary and Conclusions
Regional development is a field of study requiring policy decisions. In a purely competitive economy, markets
determine what is produced and what is consumed. Seldom do we permit markets in regions to operate
completely unregulated. Externalities of production, public good nature of infrastructure, missing markets
for amenities, and the importance of the distribution of benefits of economic growth enter into the political
process of guiding regional development. Some policymakers view area development as an end in itself,
irrespective of the results on measures of welfare for area populations.
In this chapter we presented a framework for analysis of regional development programs and policies. Markets
were defined in terms of structure and behavior. Economic behavior of producers and consumers was specified,
and ownership of resources was identified. The economic model is a form of regional general equilibrium
where prices, quantities, and incomes are endogenous and changes in regional welfare are measured.
Examples of policy applications of regional general equilibrium studies completed in Oklahoma are presented
in the next section. Examples of other studies are referenced in Partridge and Rickman. The last section is a
summary and conclusion for this chapter of the webtext.
6.1
Policy applications
This section summarizes studies of regional welfare change associated with development issues by means
of regional CGE. The first study is a state-level analysis of welfare losses due to agricultural export price
decreases in the 1980s. Results explain why state policymakers were anxious to replace regional welfare losses.
The second study is an effort to show the state economic impacts of potential damages a change in surface
water quality may have on sport fishing in Oklahoma. The models are not presented, but are available in
references cited.
6.1.1
Agricultural export prices4
Agricultural commodity prices showed a sizable decrease during the mid1980s. Farm foreclosures and
bankruptcies were several times higher than normal for the state. Low agricultural commodity prices and
depressed energy prices decreased income and employment levels throughout the state, particularly in rural
areas.
From 1982 to 1986 there was about an 11 percent decrease in export prices of agricultural commodities. In
this context, a counterfactual experiment of a 10 percent decrease in export (national) prices of agricultural
commodities was simulated for the Oklahoma economy focusing on welfare changes by household income
group.
Welfare changes in terms of compensating variation (CV) amounted to a state loss of about $123,702,000 at
the 1990 price level. Welfare losses equaled $83,525,000 for the high income household group and $51,281,000
for the middle income household group. Low income households showed a slight welfare gain of $11,104,000.
The latter is a result of lower commodity prices, particularly for nontradable commodities. When compared
to the initial level of expenditure for each household income group, welfare change for high income households
was –0.86 percent, middle income households was -0.26 percent, and low income households was +0.10
percent.
Most policymakers seek strategies that are short- to intermediate-term. Such strategies have limited success
because most regional development issues are structural and require long-term changes in comparative
advantage. When Oklahoma lost aggregate income and employment because of the decrease in agricultural
prices, policymakers sought to replace the loss as quickly as possible. The strategies proposed, however,
were long-term. Investments in value-added activities, international trade development, and development
of alternative crop and livestock enterprises require long-term commitment – results of such development
strategies are not felt immediately. Rural development research has not adequately recognized the differences
4 This section draws on the methods and results presented in Koh and Lee. The basic regional general equilibrium model
is available in Koh, Schreiner, and Shin but was modified by Lee to include a labor migration elasticity, the labor-leisure
relationship, and measures of welfare change. The basic social accounting matrix also was updated to 1990.
43
between proposed development strategies and policy expectations. In part this is because rural development
research has not focused on how factor and commodity markets work in rural regions in the short to
intermediate term versus the long term.
The regional equilibrium model developed and applied at the state level in this study simulates the short-run
conditions for markets by holding land and capital fixed by sector. Labor is assumed mobile between
sectors and between regions. Hence, simulation results approach the short- to intermediate-term effects that
correspond with expectations of policymakers.
A major conclusion of the study is that resource owners have a large stake in the re-establishment of economic
activity. Land owners had a 20.9 percent reduction in land rents, and capital owners had a reduction of
capital rents ranging from 20.9 percent in agriculture to 0.5 percent in services. Labor compensation was
reduced 0.5 percent which, because of mobility between sectors and regions, was significantly less than the
losses by land and capital resource owners. Labor that migrated had the lowest loss in resource compensation.
6.1.2
Sport fishing trip demand5
Growth in sport fishing and the associated increase in angler expenditures have heightened the need for
understanding how variations in expenditure can affect a regional economy and the welfare of economic
participants. In Oklahoma the number of anglers increased 14 percent from 1980 to 1990, compared to a 20
percent increase nationally. Fedler and Nickum estimate that angler expenditure in Oklahoma was $387.3
million or 0.6 percent of gross state product in 1991. The fixed price multiplier impact was estimated by
Fedler and Nickum to equal $793.5 million in output for all Oklahoma sectors, $202.2 million in job earnings,
and 11,606 in employment. But what are the general equilibrium results, when both price and quantity
are endogenous, from a change in the demand for sport fishing trips? Such general equilibrium results are
important for measuring policy implications of changes in quality of sport fishing and subsequent changes in
trip demands.
Agriculture accounted for about 5 percent of gross state product (GSP) in Oklahoma in 1992. Scifres and
Osborn estimate that 15.4 percent of GSP is associated directly and indirectly with agriculture. Natural
resource systems provide valuable services in support of agricultural production and sport fishing activities.
Boosting agricultural production by applying more fertilizer and other chemical products could substantially
affect the quality of water in natural resource systems and negatively impact sport fishing.
This study utilizes information on sport fishing trips and sport fishing expenditures in Oklahoma to measure
welfare gains/losses due to a change in trip demand. The National Survey of Fishing, Hunting and Wildlife
Associated Recreation shows that 803,700 U.S. anglers fished in Oklahoma during 1991 with a total angler
expenditure of $387,326,000.
Model experiments focused on decreased trip demands. The premise is that if quality of sport fishing decreases,
trip demand decreases. Quality of sport fishing is hypothesized to be associated with number of fish caught
per trip. The number of fish caught per trip is hypothesized to be associated with fish population which, in
turn, is hypothesized to be associated with water quality. Hence, a decrease in water quality (i.e., an increase
in chemical discharge) reduces fish populations which reduces fish caught per trip and thus decreases the
quality of sport fishing and number of trips in Oklahoma. Presumably anglers have alternative sites outside
of the state at which they can replace their desire for sport fishing. These experiments begin to address the
general equilibrium policy implications of the fixed price impact analyses by Fedler and Nickum for sport
fishing expenditures and by Scifres and Osborn for cash receipts of agriculture.
Two scenarios were analyzed: a 10 percent and 50 percent quality tax imposed on the price (costs) of in-state
trips. This increases the cost of in-state relative to out-of–state trips. Regional welfare was measured by
gross state product and household welfare. Loss in GSP with a 10 percent quality tax on in-state fishing
trips was estimated at $14,910,000 and at $55,670,000 with a 50 percent quality tax. These loses are due to
outmigration of resources and lower resource returns (wage rate and capital and land rents).
5 This section draws on methods presented in a paper for the Sixth International CGE Modeling Conference (Budiyanti,
Schreiner, and Li) and on modeling methods in Lee. Results are from Budiyanti.
44
A more revealing welfare measure was the compensating variation loss to households. This loss is a measure
of the income it would take to bring households back to their original level of welfare before the fishing trip
quality tax. The distribution of welfare loss showed that high income households had the greatest percentage
loss when compared to the before quality tax income level. Low income households had a higher percentage
loss compared to middle income households. The 50 percent quality tax had about four times the percentage
welfare loss compared to the 10 percent quality tax. If a dollar of welfare loss is valued equally across the
household income groups, then for all households in the state the welfare loss was $16,556,000 with the 10
percent quality tax and $64,070,000 with the 50 percent quality tax.
6.2
Summary and conclusions
We need better analyses of regional development programs and policies as they impact the welfare of
households. We need better and more integrated policy frameworks in which to perform analyses. We need
better analytical models to evaluate programs and policies that allow prices, quantities, and incomes to be
endogenously determined for regions. We need more and better regional data including estimates of structural
parameters.
Regional economies are characterized by complex variable interdependencies and market interactions. This
makes the general equilibrium framework a more appropriate analytical method compared to partial equilibrium methods. In this chapter, an attempt was made to present the salient features and a step-by-step
illustration of the implementation of a regional computable general equilibrium (CGE) model. Because of the
rigid nonsubstitution assumptions and absence of the role of price in alternative general equilibrium models,
such as input-output and SAM multiplier models, we argue that the more flexible and theoretically sound
CGE approach is the more appropriate framework of analysis.
A typical CGE model incorporates the core of neoclassical features of a well functioning economy that is
characterized by perfectly competitive markets and constant returns to scale production technologies. This
chapter has demonstrated CGE modeling for such an economy, using Oklahoma’s 1993 social accounting
matrix (SAM). Because this material is intended for a wide range of readership – including upper-class
undergraduate students, graduate students, and practitioners – several additional assumptions have been
adopted to simplify the scope and size of the model. For example, the Oklahoma regional economy is
aggregated into four industrial sectors, and a single household income group. Also, local, state and federal
governments are all represented by a single government institution. Household commodity demand functions
are assumed to be derived from a non-leisure-augmented Stone-Geary (linear expenditure system) utility
function. The aggregated Oklahoma CGE model was used to simulate an increase in terms of trade. Results
of the simulation were used to interpret the workings of regional CGE.
While the assumptions adopted in this model help to reduce the scope and complexity of the model to levels
that are relatively easy to comprehend, such ideal economies seldom exist in reality. Relaxing some of the
assumptions of this basic structure is likely to result in a more representative picture of the economy. However,
the general modeling techniques remain the same. In section 5.0 of this chapter, a monopsonistic market
structure was proposed for the forest products industry and the model was respecified. We encourage the
readers to extend the basic model in ways to address real world regional impact and policy problems.
Although a CGE model is generally theoretically sound, it is not clear whether its quantitative predictions
are superior to alternative models. Most of the specification problems in CGE analysis emanate from its
reliance on one year of data implied by the calibration process. This tends to make the system underidentified,
making it imperative for the researcher to use external parameters, which in most cases are estimated in a
framework that is inconsistent with general equilibrium analysis.
45
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Rickman, D. “Estimating the Impacts of Regional Business Assistance Programs: Alternative Closures in
Computable General Equilibrium Model.” Regional Science, 71,no.4(1992):421-435.
Robinson, S. Using and Updating IMPLAN Data for State and Regional Computable General Equilibrium
Models (1996). Paper Presented at the 1996 IMPLAN Users Symposium, August 15-17, 1996, Minneapolis,
MN., 1996.
Robinson, S., M. Kilkenny, and K. Hanson. “The USDA/ERS Computable General Equilibrium (CGE) Model
of the United States.” Staff Report No AGES 9049, Agricultural and Rural Economy Division , Economic
Research Service, USDA, 1990.
Rogers, R. and R. Sexton. “Assessing the Importance of Oligopsony Power in Agricultural Markets.” American
Journal of Agricultural Economics 76(December, 1994):1143-1150.
Rose, A. Z. Natural Resource Policy and Income Distribution. Baltimore: Johns Hopkins University Press,
1988.
Sadoulet, E., and A. de Janvry. Quantitative Development Policy Analysis. Baltimore: The John Hopkins
University Press, 1995.
Scifres, C. and J. Osborn. Oklahoma Agricultural Production Trends. Stillwater, OK: Oklahoma Agricultural
Experiment Station Bulletin B-936, No. 805, 1983.
Schreiner, D., H. Lee, Y. Koh, and R. Budiyanti. “Rural Development: Toward an Integrative Policy
Framework.” The Journal of Regional Analysis and Policy, Vol. 26, no. 2(1996):53-72.
Seung, C., T. Harris, and R. MacDiamid.. “A Comparison of Supply-Determined SAM and CGE Models.”
The Journal of Regional Analysis and Policy, 27(1997):55-71.
Stone, J. R. N. “Linear Expenditure Systems and Demand Analysis: An Application to the British Demand.”
Economic Journal, 64(1954):511-527.
Sullivan, B., D. McCollum, and G. Alward. 1996. “Regional CGE Models Based On IMPLAN Social Accounts:
Experiments in Arizona and New Mexico.” Paper Presented at the 1996 IMPLAN Users Symposium, August
15-17, 1996. Minneapolis, MN.
Tembo, G. “Duality in Computable General Equilibrium Modeling: Relaxing the Constant Returns to Scale
Assumption.” Unpublished Term Report, Oklahoma State University, Stillwater, Oklahoma, 1997.
Tembo, G., E. Vargas and D. Schreiner. “Sensitivity of Regional Computable General Equilibrium Models
to Exogenous Elasticity Parameters.” Paper presented at the Mid-Continent Regional Science Association
meetings, June 10-12, 1999, Minneapolis, MN.
Theil, H. “The Information Approach to Demand Analysis.” Econometrica, 33(1965):67-87.
Tillman, A. D. Forest Products Advanced Technologies and Economic Analyses, Orlando: Academic Press,
Inc., 1985.
Treyz, F. and J. Bumgardner. “Monopolistic Competition Estimates of Interregional Trade Flows in Services.”
REMI Mimeograph. Amherst, MA: Regional Economic Models, Inc. 1996.
Varian, H. R. Microeconomic Analysis, Third Edition. New York: W. W. Norton & Company, Inc. 1992.
Vargas, E., and D. Schreiner. “Modeling Monopsony Market With Regional CGE Model: The Oklahoma
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48
Villar, A. General Equilibrium with Increasing Returns. Springer-Verlag Berlin Heidelberg, 1996.
Whalley, J. and I. Trela. Regional Aspects of Confederation. Buffalo: University of Toronto Press, 1986.
49
List of Tables and Figures
2.1 Aggregated Social Accounting Matrix(SAM) for Oklahoma, 1993($1,000) or pdf file of Table 2.1 and
Tables 2-6
3.1 Elasticities of Import Substitution
3.2 Elasticities of Transformation
4.1 Competitive CGE Model Equations
4.2 Subscript Notation
4.3 Summary of Endogenous Variables
4.4 Summary of Exogenous Variables
4.5 Summary of Parameters
4.6 Effects of a 5% Change in Terms of Trade, Oklahoma, 1993
Figure 2.1 An Illustrative Social Accounting Matrix
50
Table 4.2
Subscript Notation
INDEX Description
i, j
Sectors and Commodities
AGR agriculture
MIN mining
MAN manufacture
SER services
ag
Agricultural sectors
AGR
nag
Nonagricultural sectors
MIN, SER, MAN
f
Factors of production
L labor
K capital
T land
fl
Factors not land
L, K
51
VARIABLE
Z
PL
PK
PKL
PT
PN
PR
P
PX
LAB
CAP
LAND
TCAP
TLAB
LS
LMIG
KMIG
VA
V
VM
VR
R
X
EXP
M
TVM
TVR
TV
adjL
LY
ALY
KY
TY
YENTt
RETENT
YH
DYH
HSAV
SAV
INV
YGOV
IBTX
GRP
AHEXP
Q
QM
QR
GOVEXP
QGOV
Table 4.3
Summary of Endogenous Variables
DESCRIPTION
Objective Function Value
Wage Rate
Capital rate in short-run
Capital rate in the long run
Land rent
Net price
Regional price
Composite price faced by consumers
Composite price faced by producers
Labor demand
Capital demand
Land demand
Total Capital Demand
Total Labor Demand
Labor supply
Labor migration
Capital migration
Value added
Composite intermediate good demand
Imported int good demand
Reg int good demand
Regional supply
Outpost
Export
Import
Imported int good total demand
Reg int good total demand
Composite intermediate good total demand
Labot adjustment
Labor income (original hhs)
Adjusted labor income (staying + in-migtation)
Capital income (original capiyal stock)
Land income
Enterprise income
Retained Earnings by enterprises
Income of hh staying in the region (including in-migrants
Disposable hh income (staying in the region + inmigra)
Household saving (staying + inmigrat)
Total saving
Investment
gov revenue
Indirect business tax
Gross region product
Adjusted household expenditure (spent within the region)
Demand for comp consump good
Demand for imp consump good
Demand for reg consump good
gov expend
gov demand for comp good
52
NUMBER
1
1
n
1
1
n
n
n
n
n
n
1
1
1
1
1
1
n
nXn
nXn
nXn
n
n
n
n
n
n
n
1
1
1
1
1
1
1
1
1
1
1
1
1
n
1
1
n
n
n
1
n
VARIABLE
QGOVM
QGOVR
QINV
QINVM
QINVR
SLACK
SLACK2
Table 4.3
Summary of Endogenous Variables
DESCRIPTION
gov demand for imported good
gov demand for reg good
Invest gov demand for comp good
Invest gov demand for imported good
Invest gov demand for reg good
Slack variable
Slack variable
53
NUMBER
n
n
n
n
n
n
n
VARIABLE
PLROC0
PKROC0
PE0
PM0
LS0
LHHH0
LGOV0
KS0
TS0
ROWSAV0
TRGOV0
REMIT0
GOVITR0
GOVBOR0
QGOV0
Qinv0
Table 4.4
Summary of Exogenous Variables
DESCRIPTION
Wage rate of rest-of-country
Cap rate of rest-of-country
Export price
Import price
Labor supply by regional household
Labor employed by household grouop
Labor employed by gov
Supply of pri capital (short-run)
Supply of land
Saving from res-of-world
Gov transfer to hh
Remittance from outside the region to household
Inter gov transfer
Government borrowing
government demand for comp good
Invest demand for comp good
54
NUMBER
1
1
n
n
1
1
1
1
1
1
1
1
n
n
Table 4.5
Summary of Parameters
VARIABLE
aoi
aji
αif
φVi A
ρVi
V
δji
φVji
ρX
i
δiX
φX
i
ρGOV
i
δiGOV
φGOV
i
V
ρIN
i
IN V
δi
V
φIN
i
L
δ
δK
ktax
sstax
ttax
retr
et
hhtax
mps
ibtax
beta
DESCRIPTION
composite primary factor input coefficient
intermediate input coefficient
factor production of elasticity for product i
value added shift parameter sector i
intermediate input substitution parameter
intermediate input import share parameter
Intermediate input imort-domestic substitution efficiency parameter
market substitution parameter
output share parameter
output shift parameter
government substitution parameter
government output share parameter
government output shift parameter
investment substitution parameter
investment share parameter
investment shift parameter
Labor migration elasticity
Capital migration elasticity
capital tax rate
factor income tax rate for labor
factpr omcp,e tax rate for land
rate of retained earnings fr ent inc
enterprise tax rate
income tax rate for hh
saving rate
indirect business tax
houosehold budget shares
55
NUMBER
n
nXn
nXn
n
n
nXn
nXn
n
n
n
n
n
n
n
n
n
l
1
1
1
1
1
1
1
1
n
n
List of acronyms
Computable General Equilibrium Modeling for Regional Analysis
Eliécer Vargas, Dean Schreiner, Gelson Tembo, and David Marcouiller
AIDS
BEA
BLS
CD
CES
CET
CGE
CRS
GAMS
GRP
GSP
IMPLAN
I-O
LES
NIPA
REIS
SAM
SDSAM
VA
List of Acronyms
Almost Ideal Demand System
Bureau of Economic Analysis
Bureau of Labor Statistics
Cobb-Douglas
Constant Elasticity of Substitution
Constant Elasticity of Transformation
Computable General Equilibrium
Constant Returns to Scale
General Algebraic Modeling System
Gross Regional Product
Gross State Product
IMpact analysis for PLANning
Input-output
Linear Expenditure System
National Income and Product Accounts
Regional Economic Information System
Social Accounting Matrix
Supply-determined SAM
Value-added
56
Glossary of Terms
Armington assumption: Allows domestically produced and foreign produced goods to be imperfect
substitutes in use, making the consumption of quantities of domestically produced and imported variants of
the commodity to enter the representative consumer’s utility function as distinct elements. In empirical CGE
formulations, this assumption helps to overcome the “specialization” problem (de Melo and Tarr).
Calibration: The process by which values of the normalizing (or free) parameters are determined so as to
replicate the observed flow values incorporated in the social accounting matrix (SAM), assuming all the
equations describing the equilibrium in the system (model) are met in the benchmark period. This process is
augmented by literature search (and on occasion econometric estimation) for key model parameters, whose
values are required before the calibration can proceed. In practice, due to the wide spread use of CES
functions in applied models, “key” parameters are more or less synonymous with elasticities (Mansur and
Whalley).
Cobb-Douglas production function: A production function in which the elasticity of factor substitution
is constant and equal to unity. In general, this function has the form f (x, y) = Axα y β , where A is an efficiency
parameter, x and y are the inputs and α and β are their coefficients (which, for this function, are equal to
elasticities).
Compensating variation: An estimate in money terms of the amount households would require as
compensation in order to remain as well off after an exogenous shock as they were before the shock. This
welfare measure is based on new equilibrium prices.
Computable General Equilibrium (CGE) model: An integrated system of equations (or general
equilibrium model), derived from economic theory of the behavior of all economic agents, whose simultaneous
solution uses a numerical database to determine values of the endogenous variables. By simulating the
effects of policy, structural or market changes, a well-defined CGE model is a useful tool for economic impact
analysis.
Duality: Duality in neoclassical microeconomics refers to the existence, under appropriate regularity
conditions, of indirect (or dual) functions which embody the same essential information on preferences or
technology as the more familiar direct (or primal) functions such as production and utility functions. Dual
functions contain information about both optimal behavior and structure of the underlying technology or
preferences, whereas the primal functions describe only the latter. Many relationships that are difficult to
understand when looked at directly become simple, or even trivial, when looked at using the tools of duality
(Varian).
Equivalent variation: Defined the same as compensating variation except that this welfare measure is
based on initial equilibrium prices rather than new equilibrium prices.
ES202: A federal-state program summarizing employment, wage and contribution data from employers
subject to state unemployment laws, as well as workers covered by unemployment compensation for federal
employees (UCFE). The ES202 program is also called Covered Employment and Payrolls (CEP) program and
involves the Bureau of Labor Statistics (BLS) of the U.S. Department of Labor and the State Employment
Security Agencies (SESAs).
Externality: Side effects of an action that influence the well-being of nonconsenting parties. The nonconsenting parties may be either helped (by external benefits) or harmed (by external costs). For example, the
effect of an industry’s output on the total costs of each firm and/or other participants in the economy.
Frisch parameter: Marginal utility of income with respect to income (de Melo and Tarr).
General equilibrium model: A model of an economy that portrays the operation of many markets
simultaneously.
Hicksian demands: Demand functions that are derived from cost minimization, commonly referred to as
the dual problem in demand analysis. These functions tell us how quantity is affected by prices with utility
57
held constant. Primal to these demands are the Marshallian demands, which are derived from maximizing
utility holding income constant.
Imperfect competition: Any market structure in which firms do not exhibit the characteristics of perfect
competition.
Lagrangian: A mathematical technique used to find values of variables that minimize or maximize an
objective function while satisfying equality constraints.
Law of one price: The assumption that the price of a commodity differs between any two levels of the
marketing channel by no more than the transfer costs. For example, by this law, the price is expected to
differ between any two locations by no more than transportation costs. Implicit in this law is the assumption
of extreme specialization and perfect substitution between domestic and foreign commodities.
Leontief production function: (see Leontief technology below)
Leontief technology: A production technology in which inputs always enter in fixed proportions to produce
a unit of output (zero elasticity of factor substitution). Thus, the input that poses a binding constraint
determines the amount of output to be produced. Mathematically, Leontief technology is presented as:
f (x, y) = min(ax, by), where x and y are the inputs and a and b are their fixed coefficients.
Market distortion: Market failure that is caused by deliberate policy intervention, such as imposition of a
tax or a subsidy. [see definition of market failure below]
Market failure: Failure of the market system to attain hypothetically ideal allocative efficiency. This means
that potential gain exists that (for some reason) has not been captured.
Missing markets: Absence or incompleteness of markets for some goods and services, which renders prices
for such commodities nonexistent. For example, an agent (e.g. firm) may care about an externality (e.g.
pollution) generated by another agent but have no way to influence it.
Monopoly: A market structure characterized by a single seller of a well-defined commodity for which there
are no good substitutes and by high barriers to the entry of other firms into the market for that commodity.
Monotonically decreasing: A function g(−) is said to be monotonically decreasing if, for any x > y,
g(x) < g(y).
Monotonically increasing: A function g(−) is said to be monotonically increasing if, for any x > y,
g(x) > g(y).
Non-convexity: Non-convexity is explained by the incapacity of the additivity and divisibility hypotheses on
production to hold. The additivity assumption says that if two production plans are technologically feasible,
a new production plan consisting of the sum of these two will also be possible. Divisibility, on the other
hand, states that if a production plan is feasible, then any production plan consisting of a reduction in scale
will also be feasible. Failure of the divisibility assumption is argued as the main source of non-convexities in
production.
Oligopoly: A market structure in which there are only a few sellers of a commodity (competition among
the few).
Partial equilibrium model: A model of a single market that ignores repercussions in other markets.
Perfect competition: A widely used economic model (market structure), where it is assumed that there is
a large number of buyers and sellers for any commodity and each agent is a price taker.
Returns to scale: The term returns to scale refers to the response of output when proportional increases in
all inputs are carried out (scale of operation). If output increases by a smaller proportion, then the technology
is said to exhibit decreasing returns to scale (diseconomies), but if it increases by a greater proportion than the
inputs it exhibits increasing returns to scale (economies). If output increases by the same proportion as the
inputs, we refer to this technology as constant returns to scale. Mathematically, if f (mX) = mi f (X), k > 1,
58
implies increasing returns, k < 1 decreasing returns, and k = 1 constant returns when X is a vector of inputs,
f (X) is the production technology, and m is a scalar.
Specialization problem: The Law of One Price implies extreme specialization in an economy where goods
are produced under CRS and the number of commodities exceeds the number of factors of production.
59
Normalized prices in the commodity and factor markets
As an example, consider the services (industry) row in Table 2.1 (i.e. regionally produced services consumed
in the region or exported). The values in this row are purchases by industry, institutions and buyers outside
the region (exports). Each of these values is expressed as p • q = R, or price times quantity equals expenditure
(revenue). The only value we know in this expression is R (the value in the SAM). But if we normalize (code)
p = 1.0 then (1.0) • q = R and R can be interpreted as a quantity index of output, q.
Consider household demand (Dh ) for services. Because we know all markets are in equilibrium we can
specify the market result for household demand as in Figure 1a. The shape of the demand curve has not
been specified yet but we know that the equilibrium price-quantity combination lies on the demand curve.
The quantity is taken from Table 2.1 and equals 30,727 million units. Each of the other sources of demand
(industry, governments, capital and exports)
for services will also be in market equilibrium. Aggregate demand for regionally produced services is shown in
Figure 1b along with regional supply. Again, in equilibrium we know that regional price is 1.0 and quantity
is 59,115 million physical units (index). The shape of the supply curve has not yet been specified but we
know this equilibrium point is on the curve.
Similarly, the labor row in Table 2.1 shows the compensation for labor from industry and institutions. Because
there is only one labor market (more labor markets may be identified if labor is segmented by skill level), the
wage bill (labor compensation) is equal to wage rate times quantity of labor, w • L = W . The only value we
know in this expression is W (from Table 2.1). If we normalize w = 1.0 then (1.0) • L = W and, again, W is a
quantity index of labor, L. Because the labor market is in benchmark equilibrium, we show this equilibrium
point in Figure 2 at w = 1.0 and L = 37, 490 quantity index (million). The shape of the demand and supply
curves for labor have not yet been specified.
60
The Leontief Production Function
Remember that the SAM values in monetary units ($) can be interpreted as physical units (index) when
prices are normalized to one (click here for normalized prices). For agriculture, the isoquant relationship
showing the combination of composite factor inputs to composite intermediate inputs in attaining X o output
is shown in Figure 1. From equation (3.1.1), producers would always choose the minimum input to obtain
the X o output. To choose any point on the X o isoquant other than point A would increase the quantity of a
costly input without increasing output. Furthermore, producers would always combine the inputs in the ratios
of Va0A and aVℓ no matter the price of the inputs. In other words, because the inputs are not substitutable in
obtaining X o , any price ratio between the inputs will always go through point A.
Production Elasticities
In the Cobb-Douglas (CD) production function (equation 3.1.3) we define the production elasticity for labor
as:
L
Z
T
∂V A LAB
•
= αL φV A LAB (µ −1.0) • CAP µ • LAN Dµ
∂LAB V A
•
LAB
VA
and simplifying,
∂V A LAB
•
= αL
∂LAB V A
Therefore, the production elasticity is constant and equal to the production parameter αL . Thus, a one
percent change in the quantity of labor (ceterus paribus, capital and land constant) used in production for
the ith sector results in an αL percent change in net output.
Similarly, the production elasticities for capital and land in producing net output for the ith sector are αiL
and αiT , respectively.
61
Profits
Profit is defined as total revenue (T R) minus total cost (T C). In the competitive model, there are zero
profits. Using previous information on normalized price, T R for agriculture (sector 1) (Table 2.1) is
P X1 • X1 = $4, 344, 000, 000. Total cost (T C) for agriculture is:
T C1 =
4
X
j=1
Pj aj1 X1 + P L • LAB1 + P K1 · CAP1 + P T • LAN D1 + ibt1 P X1 • X1
(1)
where Pj is the price of the intermediate input from sector j, ajl Xl is the agricultural sector’s requirement for
intermediate inputs from sector j to produce one unit of output Xl (note the relationship in equation 3.1.2),
P L is the wage rate, LAB1 is labor in agriculture, P K1 is the unit capital return in agriculture, CAP1 is
capital in agriculture, P T is land rent, LAN D1 is land in agriculture and ibt1 is per unit indirect business
tax rate in agriculture (value).
Because intermediate inputs and indirect business tax are fixed ratios of sector output (equation 3.1.2), a net
price of output can be defined as:
X
Pj aj1 − ibti • P Xi
(2)
P Ni = P Xi −
1
Net price is interpreted as the unit value of output available for compensating primary factors of production.
For agriculture, the net price is: P N1 = 1.0 − 0.40 − 0.02 = 0.58 (using benchmark data).
The profit function is:
π1 = T R1 − T C1
(3)
By substituition,
X
X
Pj a1j X1 −P L • LAB1 −P K1 • CAP1 −P T • LAN D1 −ibt1 • P X1 • X1
Pj a1j +ibt1 P X1 )X1 −
π1 = (P N1 +
1
1
= P N1 • X1 − P L • LAB1 − P K1 • CAP1 − P T • LAN D1
This is the same as equation (3.1.6) in the text.
62
Graphic Presentations of the Calibrated CD Production Function and Factor Demands
After calibrating the production function (equation 3.1.5) and factor demands (equations 3.1.12 to 3.1.14),
we can visualize the form of these functions. With calibrations, the Cobb-Douglas value-added (net product)
production function (3.1.15) becomes:
Xi = 7.46 • LABi0.253 • CAP10.333 • LAN D10.414
The figure below shows the demand functions for the three factors – labor, land and capital – for the
agricultural sector.
Figure: Factor demands for agriculture
The process of generating the function from the calibrated equations also helps to validate the calibration
process. If there are no mistakes in the process of determining the parameters, initial values from the SAM
are obtained when initial values of the variables are used. For example, in the above figure, the three demand
functions should display the initial SAM levels for factor demands when the (normalized) unitary price is
used. This should be true for all components of the CGE model. If this is not true, then accuracy in the
calibration of the parameters should be checked.
The figure below shows two production functions relating labor to output in agriculture while holding capital
and land constant. In the first schedule, the base-year value of each parameter is assumed. In the second
schedule, technical efficiency improvement is assumed.
Figure: Production functions for agriculture with capital and land constant
By using the benchmark schedule (base technology), the base year (SAM) value of output (4,344,160,000) is
obtainable by reading on the vertical axis the value corresponding to the benchmark level of labor (433,242,000).
Because of truncating the calibrated parameters in the production function the output value may not be
exactly the same as in the SAM. However, when calibrating the parameters for the algorithm solution, the
parameter values will not be truncated and results will be more consistent with initial SAM values.
Improved technology (neutral with respect to inputs) was introduced into the above production function by
multiplying the efficiency parameter (φCX ) by 1.1. As expected, this alteration caused the curve to shift
upward. Note that other conditions can be expressed using the partial equilibrium analysis. For example,
one can introduce change in the share parameters or the elasticities of substitution.
63
Graphic Presentation of the Calibrated
CES Function for Domestic and Imported Intermediate Inputs
V
Using the calibrated values for manufacturing inputs to the agricultural sector, δji
= 0.57, φV =
ρr
φV
V
V
V
1.93; and PjV = 0.72 the following CES function; Vji = φVji [δji
V Mji1 + (1 − δji
)V Rjij ]1/ρ1 is graphed (figure
below).
Figure: Substitution between regionally produced and imported manufacturing intermediate
inputs into the agricultural industry
Increasing the substitution parameter by 30 percent in the above figure decreases the curvature of the
relationship. This is the a priori expectation, that the greater the degree of substitution, the more linear the
result. The two schedules in the figure are tangent at the base quantities of imported and regionally produced
intermediate inputs, indicating that the calibration was accurate.
Modeling substitution among labor skills
The labor skill CES function for industry i is given as:
1
LABi = φLAB
i
X
ρLAB
LAB
∂is
LDis1
s
σ1LAB
, ρLAB
=
i
σiLAB − 1
σiLAB
(1)
where ρ LAB
=
substitution parameter among labor skills, φLAB
> 0 is the labor efficiency parameter,
6 0 is the P
i
i
LAB
LAB
LAB
∂is (0 < ∂is
< 1, ∂is
= 1) is the share parameter for labor with skill s, LDis is the quantity
demanded of that skill type, and σiLAB is the elasticity of substitution among labor skills.
The derived demand for labor skill s in industry i is based on cost minimization to satisfy the aggregate
labor
requirement in the industry. Thus, the producers want to choose the level of LDis so as to minimize
P
•
s P LSs LDis
1
subject to: LABi = φLAB
i
P
P
s
ρLAB
LAB
LDis1
∂is
ρ1LAB
where s P LSs LDis is the total wage bill, P LSs is the wage rate of labor of skill s. First order conditions
of this problem result in
•
LAB
P LSs = φLAB
i
X
ρLAB
1
LAB •
∂is
LDis
s
64
1
1−σLAB
σ
1
−(1−ρLAB
i
LAB •
∂is
LDis
)
(2)
From equation (2), the ratio of wages for two labor skills of type s and t can be expressed as:
−(1−ρLAB )
1
P LSt
∂ LAB • LDit
= it
LAB ) , or
−(1−ρ
P LSs
1
LAB • LD
∂is
is
LDis =
LAB
P LSs • ∂it
LAB
P LSt • ∂is
(3)
1
1+ρLAB
1
(4)
By substituting equation (4) into equation (1), the skill-augmented labor demand equations become
LABi = φLAB
i
"
X
LAB
∂is
s
LAB
P LSs ∂it
LAB
P LSt ∂is
ρLAB
i
(1−ρLAB )
1
LDit
#
1
ρLAB
1
(5)
Thus, by using equations (4) and (5), it can be shown that the demand for labor of type s has the form
LDis
LABi = LAB
φi
"
X
s
LAB
∂is
LAB
P LSs ∂it
LAB
P LSt ∂is
ρLAB
1
(1−ρLAB )
1
#
1
ρLAB
1
(6)
Calibration of the labor substitution relationships discussed in this section involves obtaining each sector’s
estimate of the elasticity of substitution from external sources. Equation (4) can be used to compute the
value of the labor skill share parameters by normalizing the prices to one and rearranging the terms. The
base year quantities of the labor skills, if available, are presented in the SAM. The SAM used in this paper,
however, does not differentiate labor by skill. We will leave calibration of this section to the interested reader.
An example of a social accounting matrix that differentiates labor by skill type is in Budiyanti.
Graphic Presentation of the Calibrated CET Function for Regional Product and Exports
The figure below shows an example of a market possibility frontier (for agriculture sector) for regional and
export markets, using benchmark and counter factor parameter data.
By increasing the substitution parameter by 60 percent, the market possibilities frontier becomes more
concave, which is in accordance with a priori expectations. The two schedules in the figure are tangent at
the same benchmark (SAM) quantity exported and quantity marketed regionally, an indication that the
calibration was accurate.
Figure: Market possibility frontier for the agricultural sector
65
Graphic Presentation of the Calibrated Commodity Demand
Using the calibrated budget share for agriculture, the demand schedule is obtained by varying the price and
computing the corresponding quantities using equation (3.2.16). The figure below shows the relationship for
household demand for agricultural commodities.
Figure: Household demand schedule for agricultural commodities.
The LES with Leisure and Positive Minimum Consumption
Following de Melo and Tarr, the Klein-Rubin utility function can be modified to incorporate leisure for each
household group (M = composite market goods composed of imports and regionally produced):
X
βih ln(Qih − γih )
(1)
U = β0h ln(Q0h − γσh ) +
ieM
In equation (1), the worker-consumer is assumed to purchase a combination of leisure (Q0h ) and composite
market commodities (Qih ). To derive the LES, equation (1) is maximized subject to the household’s full
income (F Yh ), which is equal to non-labor income plus imputed value of time (equation 2):
F Yh = YN L + ωTh = Yh + ωQ0h
where Yh =
m
P
(2)
pi Qih is household money income, which is also equal to HEh ; YN L is non-labor income;
i
and ωTh is the imputed value of time (ω is the imputed unit value of time and Th is total time available to
the household for work and leisure). The subscript m represents the number of commodities. Because of
considerations for leisure and non-market commodities in equation (1), the resulting LES is augmented as
follows:
n
X
β0h
Pj γjh
(3)
Q0h = γ0h +
F Yh −
ω
j=0
Qih = γih +
βih
Pi
F Yh −
n
X
j=0
Pj γjh
(4)
where P0 is the wage rate (ω). Expenditure on the ith commodity consists of expenditure on the minimum
required quantity for that commodity plus the proportion of the budget which is left over after paying for all
minimum requirements. This proportion, βi , is the marginal budget share that determines the allocation of
supernumerary income. If leisure is ignored, only composite commodities would be purchased with money
(not full) income.
66
Substitution of equation (2) into equation (3) and rearranging terms results in the household labor supply
function (see de Melo and Tarr and Lee for details of the derivations):
LSh = M Th −
β0h
ω
HEh −
n
P
j=1
Pj γjh
(5)
1 − β0h
where LSh + Q0h = Th , M Th = Th − γ0h is the maximum work time available to the household, HEh = Yh ,
and ω = P0 . Similarly, substituting equation (2) into (3) and rearranging terms provides demand functions
for market commodities by the household group, h:
Qih = γih +
βih
(1 − β0h )Pi
HEh −
n
X
Pj γjh
j=1
(6)
Equations (5) to (6) are the final formulations that constitute the household demand system.
To evaluate these equations, the parameters β0h , βih , and γih need to be calibrated using data from the social
accounting matrix (Table 2.1), a Frisch parameter, income elaticities of demand, and income elasticity of
labor supply.
First, β0h is calculated from the formula for the income elasticity of labor supply
to equation (5):
−β0h HEh
δhLH =
(1 − β0h )wLSh
∂LSh
∂HEh
•
HEh
LSh
and applying
(7)
where δhLY is available from other studies. Like other prices, w is normalized to one in the base. The variables
HEh and LSh are obtained from the SAM. Rearranging terms in (7) yields the expression used to obtain the
value of the marginal budget share for leisure, β0h :
β0h =
ωLSh δhLY
ωLSh δhLY − HEh
(8)
In the 1993 SAM (Table 2.1), for example, HEh = 50, 665, 679, 000, which is the households column/expenditure total (53,880,000,000) less government taxes (6,976,571,000), less households’ payment for
labor services (107,070,000 and less household savings –(3,869,320); and LSh = 37, 489, 772, 000 – the labor
row/income total. Using these data and a household labor supply elasticity of –0.18 (negative, implying
leisure is a normal good) equation (8) is used to calculate β0h = 0.1175. As usual, w and other prices are
normalized to one in the base year.
From the commodity demand equation (6), the elasticity of demand for commodity i with respect to income,
whose value is also obtained from previous studies, is given by:
δhY =
X
βih HEh
,
βih = 1
(1 − β0h )Pi • Qih
(9)
Given the value of β0h from (8), the only unknown in (9) is βih , the marginal budget share for commodity i.
Pi is normalized to one and the remaining values in the equation are obtained from the SAM. By rearranging
(9), we obtain an expression used to calibrate the value of the unknown,
βih =
(1 − β0h )Pi • Qih δhY
HEh
(10)
An exogenously determined Frisch parameter is used to compute the minimum subsistence requirement for
commodity i. The Frisch parameter, which is a measure of the marginal utility of income, is given as
Frisch =
HEh
P
HEh − j Pi γjh
67
(11)
Substituting (11) into (6) and rearranging terms gives an expression for calibrating γih , the minimum
subsistence requirement:
βih
HEh
γih = Qih +
(12)
(1 − β0h )Pi
Frischh
The maximum number of hours available for work M Th , which is equal to total time endowment Th (24
hours minus time necessary for sleeping and other minimal maintenance tasks) less minimum requirement for
leisure, is calibrated by rearranging (5):
M Th = LSh +
Sector
Agriculture
Mining
Manufacturing
Services
Income elasticity of labor supply
Frisch parameter
β0h
ω
HEh −
n
P
j=1
Pj γjh !
1 − β0h
Income elasticity of demand
0.30
0.89
1.06
1.05
(-0.18):
(-1.60):
(13)
Source
deMelo and Tarr
deMelo and Tarr
deMelo and Tarr
deMelo and Tarr
Abbot and Ashenfelter
Lluck, Powell and Williams
Graphic Presentation of the Calibrated Household Indifference Curve Between Regionally
Produced and Imported Commodities
A graphical presentation of the substitution relationship between imported and regionally produced commodities is shown in the form of a household indifference curve. The figure below illustrates this relationship
for agricultural commodities.
Figure: Household indifference curve between regionally produced and imported agricultural
commodities
68
Hypothetical Examples of Labor Migration
Results of equation (3.3.23) are shown for two hypothetical examples. The first shows outmigration where
the results of equation (3.3.3) is LM G = -9. Let us assume that LSO = 30, regional labor demand is
(LDI + LDE) = 21, P LE = 1.0 and P L = 0.9. Results of equatioin (3.3.23) are:
p
p
2
2
LY = 0.9(21) + 1.0
(−9) − (−9) 0.5 − 0.9
(−9) + (−9) 0.5 = 27.9
The first term on the right is regional labor compensation and is equal to 18.9. The second term is
compensation for labor that migrated out of the region and equals 9.0. The third term identifies inmigration
and is equal to zero. The original regional households had a labor supply of LSO = 30 of which 21 units
were compensated at the regional price of 0.9 and 9 units were compensated at the out-of-region price of 1.0.
Therefore the original households had labor income of 27.9 of which 18.9 was earned in the region and 9 was
earned outside the region after outmigration.
The second example shows inmigration where LM G = 9. Again we assume that LSO = 30, regional labor
demand is (LDI + LDE) = 39, P LE = 1.0 and P L = 1.1. Results of equation (3.3.23) are:
p
p
2
2
+9 − (+9) 0.5 − 1.1
+9 + 9 .5 = 33.0
LY = 1.1(39) = 1.0
Regional labor compensation is 42.9 There is no outmigration and compensation to inmigrants is 9.9. The
original households with labor of 30 units were compensated at the regional wage rate of 1.1 or 33 monetary
units. Results of equation (3.3.23) show that it holds for both outmigration and inmigration of labor. Equation
(3.3.3) is the deciding factor of migration.
69
Table 2.1: Oklahoma Social Accounting Matrix, 1993 in thousands of dollars.
EXPENDITURES
Agriculture
Mining
Forestry
INDUSTRY
FPI
Manufacturing Services
Total
Labor
FACTORS
Capital
Land
Total
Enterprise
Households
INSTITUTIONS
Governments Capital
Total
Exports
ROW
TOTAL
INDUSTRY
Agriculture
870862
8116
4936
2668
820923
34800
1542305
147210
12863
9780
169053
2591601
4303759
Mining
122579
2180942
891
85705
1192412
881343
4443872
1587998
231250
19097
1838345
5807568
12089785
9839
72630
1264
179590
206456
475805
138648
96782
248026
483456
826339
1785600
Forest Complex
40400
Forestry
FPI
6026
40400
40400
Manufacturing
147584
1318071
984
109769
3299584
3746744
8622736
2517437
1757284
4503431
Services
379945
1317332
1597
275941
4996845
9752027
16723087
30727365
1477994
557652
1330809
4897091
9672
499909
10489354 14621370
31848205
35118658
3576173
5337986
Labor
426998
1622808
6244
188400
7389027 20767388
30400863
107070
6981839
Capital
566973
2713109
4387
525780
3499379 12042709
19352337
Land
701385
Sub-total industry
8778152 15003939
32763011
9629092
32404827
59115191
44032817 33858539 109739561
FACTORS
Sub-total
1695356
7681
4335915
18312
7088909
37489772
19352337
708066
714180
10888406 32810097
709066
50462266
107070
6981839
7088909
11490516
13224750
8477813
57551175
INSTITUTIONS
Enterprises
Households
Governments
95405
866971
896
85720
101159
4318042
5268193
12510953
12510953
31363057
7848069
683300 39894426
6126715
-1006686
25766
5145795
Capital
Sub-total Institutions
35405
666971
896
85720
101159
574915
5160
11222
1274869
4955
1230
628
16247
37489772
19352238
709068 57551174
12510953
1734234
1699623
11490516
9077096
3869320
12510953
3107251
19968329
4318042
5268193
377192
41300
1004752
181550
20097
294847
385272
1983085
141562
29912
7600825
53880001
17154007
4375095
31943090
5207776
2789519
7997295
35586533
7925439 106331339
10447
212094
1216846
15759
187333
2170418
IMPORTS
Agriculture
Mining
Forest Complex
Forestry
FPI
Manufacturing
Services
Sub-total imports
COLUMN TOTAL
27620
23552
2742
19243
436987
143637
653781
299232
43146
128560
470938
1124719
414296
427425
2171
350537
8028706
2606708
11829843
5414473
780700
2326243
8521416
20351259
154136
458802
1024
998534
1788176
4188764
8689436
9510103
542893
178299
10231295
16920731
1182189
2189808
11520
485791
10985908
7365681
22160897
15547020
1416748
2659308
19623076
41783973
4303759 12089785
40400
1785600
53879999
3193089
7997294 106331335 41783978 315406048
32404827 59115190 109739561
37489772
19352336
709066 57551174
12510953
Table 2: Short-run Pro-competitive Simulation Results: Indexes for Selected Endogenous Variables
Sector
AGR
MIIN
RM
FPI
MAN
SER
IP
(1)
IPR
(2)
IPX
(3)
IPL
(4)
IPK
(5)
IPT
(6)
IX
(7)
IR
(8)
IEXP
(9)
IIMP
(10)
IQ
(11)
IQR
(12)
IQM
(13)
IVA
(14)
IL
(15)
IK
(16)
IT
(17)
1.00001
1.00005
1.00001
1.00007
1.02550
0.99573
1.00003
1.00007
1.00000
1.00003
1.02550
0.99772
1.00002
1.00006
1.00015
1.00015
1.00015
1.00015
1.00015
1.00015
0.99998
1.00002
1.03953
1.04920
1.00003
0.99999
0.99998
0.99996
0.99995
1.01326
1.01326
0.99992
0.99990
0.99999
1.00004
0.99994
0.99985
1.00001
1.00006
0.99974
0.99970
0.99973
0.99970
0.99975
0.99973
1.02001
0.99987
0.99986
0.99465
1.00020
1.00005
1.00173
0.99973
0.99970
1.01217
0.99965
0.99967
0.99690
0.99977
0.99980
0.99984
0.99987
1.03938
1.04904
0.99989
0.99984
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00000
1.00742
0.99997
0.99991
0.99996
0.99995
1.01326
1.01326
0.99992
0.99990
0.99802
1.00002
1.00005
1.03953
1.00000
where P, PR, PX, PL, PK, PT are composite price, regional price, output price, wage rate, capital price, and land price; X, R, EXP, IMP, Q, QR, and QM are regional output, regional
production consumed in region, export, import, composite household demand, household demand from regional production, and household import demand; VA, L, K, T are composite value
added, labor demand, capital demand, and demand for land. The I before each variable indicates index.
Table 3: Long-run Pro-competitive Simulation Results: Indexes for Selected Endogenous Variables
Sector
AGR
MIIN
RM
FPI
MAN
SER
IP
(1)
IPR
(2)
IPX
(3)
IPL
(4)
IPK
(5)
IPT
(6)
IX
(7)
IR
(8)
IEXP
(9)
IIMP
(10)
IQ
(11)
IQR
(12)
IQM
(13)
IVA
(14)
IL
(15)
IK
(16)
IT
(17)
1.00015
1.00097
1.00025
1.00131
1.06612
0.97064
1.00038
1.00067
1.00010
1.00068
1.06612
0.98486
1.00020
1.00056
1.00045
1.00045
1.00045
1.00045
1.00045
1.00045
1.00142
1.00142
1.00142
1.00142
1.00142
1.00142
0.99897
0.99881
0.99795
1.09566
1.09566
0.99912
0.99981
0.99940
0.99976
0.99842
0.99599
0.99986
0.99979
0.99975
0.99893
0.99956
0.99888
0.99991
0.99953
1.14630
0.99854
0.99942
0.96320
1.00180
1.00125
1.01426
0.99972
0.99940
1.08934
0.99881
0.99908
0.97998
1.00015
1.00042
0.99852
0.99856
1.17089
1.09643
0.99943
1.00017
0.99756
0.99759
1.16976
1.09537
0.99847
0.99920
1.00000
1.05139
0.99963
0.99989
0.99881
0.99795
1.09566
1.09566
0.99912
0.99981
0.98584
1.00017
1.00050
1.17142
1.00000
where P, PR, PX, PL, PK, PT are composite price, regional price, output price, wage rate, capital price, and land price; X, R, EXP, IMP, Q, QR, and QM are regional output, regional
production consumed in region, export, import, composite household demand, household demand from regional production, and household import demand; VA, L, K, T are composite value
added, labor demand, capital demand, and demand for land. The I before each variable indicates index.
Table 4: Regional Indexes for the Pro-Competitive Simulations, Selected Variables
Variable
Short-run
Long-run
Weighting
Quantities
Output
Export
Import
Labor demand
Capital demand
Land demand
1.00014
1.00036
0.99998
1.00013
1.00000
1.00000
1.00096
1.00195
1.00038
1.00041
1.00146
1.00000
base prices
base prices
base prices
NA
NA
NA
Prices
Output
Export
Import
Labor
Capital
Land
1.00002
1.00000
1.00000
1.00015
1.00135
1.00041
1.00022
1.00000
1.00000
1.00045
1.00142
1.00084
base quantities
NA
NA
NA
SR (base quantities)
base quantities
Table 5: Regional Impacts on Factor Payments from the Pro-Competitive Simulations
Factor
Units
Short-run
Long-run
Labor compensation
Change
Index
$ thousand
$ thousand
base = 1.0
37,500,224
10,652
1.00028
37,522,232
32,460
1.00087
Capital compensation
Change
Index
$ thousand
$ thousand
base = 1.0
19,378,463
26,126
1.00135
19,407,836
55,499
1.00287
Land compensation
Change
Index
$ thousand
$ thousand
base = 1.0
709,355
289
1.00041
709,662
595
1.00084
Value added
Change
Index
$ thousand
$ thousand
base = 1.0
57,588,042
36,867
1.00064
57,639,730
88,554
1.00154
Table 6: Regional Household Income Impact from the Pro-Competitive Shock
Units
Short-run
Household nominal
Income
Change
Index
$ thousand
$ thousand
base = 1.0
53,897,921
17,920
1.00033
53,908,295
28,295
1.00053
Composite price
Index
base = 1.0
1.00003
1.00034
Household real
Income
Change
Index
$ thousand
$ thousand
base = 1.0
53,896,304
16,303
1.00030
53,889,972
9,972
1.00019
Item
Long-run
Table 2.1: Oklahoma Social Accounting Matrix, 1993 in thousands of dollars.
EXPENDITURES
Agriculture
Mining
Forestry
INDUSTRY
FPI
Manufacturing Services
Total
Labor
FACTORS
Capital
Land
Total
Enterprise
Households
INSTITUTIONS
Governments Capital
Total
Exports
ROW
TOTAL
INDUSTRY
Agriculture
870862
8116
4936
2668
820923
34800
1542305
147210
12863
9780
169053
2591601
4303759
Mining
122579
2180942
891
85705
1192412
881343
4443872
1587998
231250
19097
1838345
5807568
12089785
9839
72630
1264
179590
206456
475805
138648
96782
248026
483456
826339
1785600
Forest Complex
40400
Forestry
FPI
6026
40400
40400
Manufacturing
147584
1318071
984
109769
3299584
3746744
8622736
2517437
1757284
4503431
Services
379945
1317332
1597
275941
4996845
9752027
16723087
30727365
1477994
557652
1330809
4897091
9672
499909
10489354 14621370
31848205
35118658
3576173
5337986
Labor
426998
1622808
6244
188400
7389027 20767388
30400863
107070
6981839
Capital
566973
2713109
4387
525780
3499379 12042709
19352337
Land
701385
Sub-total industry
8778152 15003939
32763011
9629092
32404827
59115191
44032817 33858539 109739561
FACTORS
Sub-total
1695356
7681
4335915
18312
7088909
37489772
19352337
708066
714180
10888406 32810097
709066
50462266
107070
6981839
7088909
11490516
13224750
8477813
57551175
INSTITUTIONS
Enterprises
Households
Governments
95405
866971
896
85720
101159
4318042
5268193
12510953
12510953
31363057
7848069
683300 39894426
6126715
-1006686
25766
5145795
Capital
Sub-total Institutions
35405
666971
896
85720
101159
574915
5160
11222
1274869
4955
1230
628
16247
37489772
19352238
709068 57551174
12510953
1734234
1699623
11490516
9077096
3869320
12510953
3107251
19968329
4318042
5268193
377192
41300
1004752
181550
20097
294847
385272
1983085
141562
29912
7600825
53880001
17154007
4375095
31943090
5207776
2789519
7997295
35586533
7925439 106331339
10447
212094
1216846
15759
187333
2170418
IMPORTS
Agriculture
Mining
Forest Complex
Forestry
FPI
Manufacturing
Services
Sub-total imports
COLUMN TOTAL
27620
23552
2742
19243
436987
143637
653781
299232
43146
128560
470938
1124719
414296
427425
2171
350537
8028706
2606708
11829843
5414473
780700
2326243
8521416
20351259
154136
458802
1024
998534
1788176
4188764
8689436
9510103
542893
178299
10231295
16920731
1182189
2189808
11520
485791
10985908
7365681
22160897
15547020
1416748
2659308
19623076
41783973
4303759 12089785
40400
1785600
53879999
3193089
7997294 106331335 41783978 315406048
32404827 59115190 109739561
37489772
19352336
709066 57551174
12510953
$TITLE REGIONAL CGE MODEL FOR OKLAHOMA (1993)(CRS.GMS)
$OFFSYMLIST OFFSYMXREF OFFUPPER
SETS
i
Sectors
/Agr agriculture
Min mining
Man manufacture
SER services/
ag(i)
Agricultural sectors
/ AGR/
nag(i) Nonagricultural market sectors
/ MIN, SER, MAN/
f
Factors
/L
labor, K
capital, T
land/
fl(f)
Factors not land / L, K/
ALIAS(i,j);
*#####-- DECLARATION OF BASE YEAR VARIABLES (AS PARAMENTERS)
PARAMETERS
*@Price block
PL0
Wage rate
PLROC0
Wage rate of rest-of-country
PKROC0
Cap rate of rest-of-country
PK0(i)
cap rate
PT0(ag)
Land rent
PE0(i)
Export price
PM0(i)
Import price
PR0(i)
Reg price
P0(i)
Composite price
PN0
Net output price or value-added price of sector i
PX0(i)
Composite price face for producers
*@Production block
L0(i)
Labor demand
LS0
Labor supply by hh
TLS0
Total labor supply
LHHH0
Labor employed by household group
LGOV0
Labor employed by gov
K0(i)
capital demand
T0(i)
Land demand
KS0
Supply of pri capital
TKS0
Total pri capital supply
TS0
Supply of land
VA0(i)
Value added
V0(j,i)
Composite intermediate good demand
TV0(i)
Composite intermediate good total demand
VR0(j,i)
Reg int good demand
VM0(j,i)
Imported int good demand
TVR0(i)
Reg int good total demand
TVM0(i)
Imported int good total demand
IBT0(I)
Indirect business taxes
X0(i)
Sector output
E0(i)
Export of reg product
M0(i)
Import
R0(i)
Reg supply of reg product
*@Income block
LY0
KY0
TY0
YENT0
YH0
DYH0
HSAV0
SAV0
ROWSAV0
TRGOV0
REMIT0
YGOV0
ENTY0
GOVITR0
GOVBOR0
GRP0
Labor income
capital income
Land income
Gross Enterprise income
Household income
Disposable hh income
Household saving
Total saving
Saving from rest-of-world
Gov transfer to hh
Remittance from outside the region to household
Gov revenue
Enterprise income distrib to hhs
Inter gov transfer
Government Borrowing
Gross regional product
*@Expenditure block
HEXP0
Household expend
QR0(i)
Demand for reg consump good
QM0(i)
Demand for imp consump good
Q0(i)
Demand for comp consump good
GOVEXP0
government expenditure
QGOVR0(i)
government demand for reg good
QGOVM0(i)
government demand for imported good
QGOV0(i)
government demand for comp good
QInvR0(i)
Invest demand for reg good
QInvM0(i)
Invest demand for imported good
QInv0(i)
Invest demand for comp good
INV0
Total invest
*The following variables are defined as "logical variables". A logical
*variable takes the value of 1 if the condition stated is true and "0"
*if not.
*************************************
*Regional
x
x
0
0
*Import
x
0
x
*
*NZV
T
F
F
F
*ZVR
F
F
T
F
*ZVM
F
T
F
T
*************************************
0=zero, x=not zero
0
T=TRUE,
F=FALSE
ZVM(i,J)
demand
ZVR(i,J)
NZV(i,J)
non imported intermediate demand with-or-without regional interm.
ZQM(i)
demand
ZQR(i)
NZQ(i)
non imported final demand and either none or some regional final
ZGOVM(i)
ZGOVR(i)
only imported intermediate demand
both imported intermediate demand and regional demand
only imported final demand
both imported final demand and regional final demand
NZGOV(i)
ZInvM(i)
ZInvR(i)
NZInv(i)
*#####-- DECLARATION OF PARAMETERS TO BE CALIBRATED.
PARAMETERS
*This parameters are those specified in Table 5.5.
*@Production block
a0(i)
composite value added req per unit of output i
a(j,i)
req of interm good j per unit of good i
Alpha(i,f)
value added share param
Ava(i)
value added shift param
RHOv(i)
interm input subs param
deltav1(j,i)
deltav(j,i)
interm input share param
Av(j,i)
interm input shift param
RHOx(i)
output transformation param
deltax1(i)
deltax(i)
output share param
Ax(i)
output shift param
*@Income block
ktax
capital tax rate
sstax
factor income tax rate for labor
ttax
factor income tax rate for land
retr
rate of retained earnings fr ent inc
et
enterprise tax rate
hhtax
income tax rate for hh
ltr
Household Income Transfer Coefficient
mps
saving rate
ibtax(i)
indirect business tax
beta(i)
param calc fr elast of comm demand wrt inc
*@Expenditure block
RHOq
consumer demand subs param
deltaq1(i)
deltaq(i)
consumer demand share param
Aq(i)
consumer demand constant eff param
RHOgov
gov demand subs param
deltagov1
deltagov
gov demand share param
Agov
gov demand constant eff param
RHOinv
inv gov demand subs param
deltainv1
deltainv
inv gov demand share param
Ainv
inv gov demand constant eff param
;
*### DATA: Data come from our SAM (Table 2.1)
Table
IOR(i,j) Input-output regional matrix
AGR
MIN
MAN
SER
;
Table
AGR
MIN
MAN
SER
AGR
MIN
675.798
123.47
159.671
381.542
IOM(i,j)
AGR
MIN
579.870
11.850
446.830
155.160
8.115
2180.942
1390.701
1317.332
MAN SER
863.991 34.800
1258.117
881.343
3594.97
3953.2
5272.186
9752.027
Input-output import matrix
MAN
SER
5.160 378.422
41.300
1274.869 311.094 385.272
450.977
8835.472
2750.345
458.802
1886.710
4188.764
;
Table VAD(i,f) Value
L
AGR
433.242
MIN
1622.806
MAN
7577.427
SER
20767.388
;
Table HHCONR(i,*)
AGR
MIN
MAN
SER
;
T
709.066
Household consumption demand for regional goods
HOUSE
147.210
1587.998
2656.085
30727.366
Table HHCONM(i,*)
HOUSE
AGR
181.550
MIN
141.662
MAN
5713.705
SER
9510.103
;
Table GOVCONR(i,*)
AGR
MIN
MAN
SER
;
added matrix
K
571.360
2713.109
4025.159
12042.708
Household consumption demand for imported goods
Government consumption demand for regional goods
GOV
12.863
231.250
1854.066
1477.995
Table GOVCONM(i,*) Government consumption demand for imported goods
GOV
AGR
MIN
MAN
SER
;
20.097
29.912
823.846
542.893
Table FYDIST(*,f) Factor income distribution to hhs
L
K
T
HH
31363.057
0.00
683.300
;
TABLE ParamA(*,i)
PT0
PK0
PR0
P0
PM0
PE0
X0
R0
E0
M0
IBT0
QINVR0
QINVM0
SIGMAv
SIGMAx
SIGMAq
SIGMAgov
SIGMAinv
BASE YEAR VALUES FOR INDUSTRY
AGR
MIN
MAN
1.00
1.00
1.00
1.00
1.00
1.00
4344.160
1752.557
2591.603
1216.846
96.301
9.780
10.447
1.42
3.90
1.42
1.42
1.42
1.00
1.00
1.00
1.00
1.00
1.00
12089.784
6282.217
5807.567
2170.418
666.971
19.097
15.759
0.50
2.90
0.50
0.50
0.50
SER
1.00
1.00
1.00
1.00
1.00
1.00
34190.427
18360.150
15830.277
21475.978
186.879
4751.457
2454.803
3.55
2.90
3.55
3.55
3.55
1.00
1.00
1.00
1.00
1.00
1.00
59115.190
49486.101
9629.089
16920.731
4318.043
557.653
178.299
2.00
0.70
2.00
2.00
2.00
;
TABLE ParamB(f,*)
BASE YEAR VALUES FOR FACTORS
WAGE0
WAGEROC0
FTAX0
RETENT0
L
1.0
1.0
6126.715
0
K
-1006.686
9077.096
T
25.766
0
;
TABLE ParamC (*,*)
HOUSE
+
HOUSE
;
HTAX0
6976.571
REMIT0
760.824
CAP0
BASE YEAR VALUES FOR HH GROUPS
HSAV0
-3869.320
TRGOV0
11490.516
ENTYDIS0
9582.303
TABLE ParamD(*,*)
BASE YEAR VALUES FOR GOVTS
BOR0
GOVDR0
GOVDM0
GOV
0.0
3576.174
1416.748
;
SCALAR LHHH0
Labor used by high inc hh / 107.070/;
SCALAR LGOV0
Labor used by government
/ 6981.839/;
1
CAPROC0
1
SCALAR
SCALAR
SCALAR
SCALAR
SCALAR
SCALAR
SCALAR
SCALAR
Scalar
GOVITR0
YENT0
ENTTAX0
ROWGOV0
ROWSAV0
QINVMSUM0
etaL
etaK
KMobil
Inter-government transfer / 8477.813/;
Enterprise income
/20359.022/;
Enterprise taxes
/ 1699.623/;
Rest of world trans.to gov. /4375.094/;
Saving from ROW
/2789.519/;
Inv demand for imported goods / 2659.308/;
Labor migr elasticity
/
0.92 /;
Capital migr elasticity
/
0.92 /;
Capital Mobility
/
1.0 /;
*@Production block
L0(i)
=VAD(i,"L");
K0(i)
=VAD(i,"K");
T0(i)
=VAD(i,"T");
VA0(i)
=sum(f,VAD(i,f));
V0(j,i)
=IOR(j,i)+IOM(j,i);
TV0(i)
=sum(j,V0(i,j));
VM0(j,i)
=IOM(j,i);
VR0(j,i)
=IOR(j,i);
TVM0(i)
=sum(j,VM0(i,j));
TVR0(i)
=sum(j,VR0(i,j));
LHHH0
=LHHH0;
LGOV0
=LGOV0;
LS0
=sum(i,VAD(i,"L"))+LHHH0+LGOV0;
X0(i)
=ParamA("X0",i);
E0(i)
=ParamA("E0",i);
R0(i)
=ParamA("R0",i);
KS0(i)
=VAD(i,"K");
TKS0
=sum(i,KS0(i));
TS0(i)
=VAD(i,"T");
IBT0(I)
=PARAMA("IBT0",I);
*@Income block
TRGOV0
=ParamC ("HOUSE","TRGOV0");
LY0
=sum(i,VAD(i,"L"))+LHHH0+LGOV0;
KY0
=sum(i,VAD(i,"K"));
TY0
=sum(i,VAD(i,"T"));
YENT0
=YENT0;
REMIT0
=ParamC ("HOUSE","REMIT0");
YH0
=sum(f,FYDIST("HH",f))+ParamC("HOUSE","ENTYDis0")+TRGOV0
+REMIT0;
DYH0
=YH0 -ParamC ("HOUSE","HTAX0");
HSAV0
=ParamC ("HOUSE","HSAV0");
HEXP0
=DYH0-HSAV0-LHHH0;
SAV0
=ParamB("K","RETENT0")+ ParamC ("HOUSE","HSAV0")+ROWSAV0;
ROWSAV0
=ROWSAV0;
YGOV0
=sum(i,ParamA("IBT0",i))+sum(f,ParamB(f,"FTAX0"))
+ParamC("HOUSE","HTAX0")+ENTTAX0+ROWGOV0+GOVITR0;
ENTY0
=ParamC("HOUSE","ENTYDis0");
GOVBOR0
=ParamD("GOV","BOR0");
GRP0
=LY0+KY0+TY0+sum(i,ParamA("IBT0",i));
*@Expenditure block
QR0(i)
=HHCONR(i,"HOUSE");
QM0(i)
=HHCONM(i,"HOUSE");
Q0(i)
=QM0(i)+QR0(i);
GOVEXP0
=ParamD("GOV","GOVDR0")+ParamD("GOV","GOVDM0")
QGOVR0(i)
QGOVM0(i)
QGOV0(i)
QINVR0(i)
QINVM0(i)
QINV0(i)
INV0
M0(i)
+ParamC("HOUSE","TRGOV0")+LGOV0+GOVITR0;
=GOVCONR(i,"GOV");
=GOVCONM(i,"GOV");
=QGOVM0(i)+QGOVR0(i);
=ParamA("QINVR0",i);
=ParamA("QINVM0",i);
=QINVM0(i)+QINVR0(i);
=sum(i,QINV0(i));
=ParamA("M0",i);
*@Price block
PL0
=ParamB("L","WAGE0");
PK0(i)
=ParamA("PK0",i);
PLROC0
=ParamB("L","WAGEROC0");
PKROC0
=ParamB("K","CAPROC0");
PT0(ag)
=ParamA("PT0",ag);
PE0(i)
=ParamA("PE0",i);
PM0(i)
=ParamA("PM0",i);
PR0(i)
=ParamA("PR0",i);
P0(i)
=ParamA("P0",i);
PX0(i)
=(PR0(i)*R0(i)+PM0(i)*M0(i))/(R0(i)+M0(i));
*---------------------------------------------------* Regional
x x 0 0
0=zero, x=not zero
* Import
x 0 x 0
*
* NZV
T F F F
T=True, F=False
* ZVR
F F T F
* ZVM
F T F T
*---------------------------------------------------ZVM(i,j)
ZVR(i,j)
NZV(i,j)
ZQM(i)
ZQR(i)
NZQ(i)
ZGOVM(i)
ZGOVR(i)
NZGOV(i)
ZInvM(i)
ZInvR(i)
NZInv(i)
=(VM0(i,j) eq 0);
=(VR0(i,j) eq 0) and (VM0(i,j) ne 0);
=(VR0(i,j) ne 0) and (VM0(i,j) ne 0);
=(QM0(i) eq 0);
=(QR0(i) eq 0) and (QM0(i) ne 0);
=(QR0(i) ne 0) and (QM0(i) ne 0);
=(QGOVM0(i) eq 0);
=(QGOVR0(i) eq 0) and (QGOVM0(i) ne 0);
=(QGOVR0(i) ne 0) and (QGOVM0(i) ne 0);
=(QInvM0(i) eq 0);
=(QInvR0(i) eq 0) and (QInvM0(i) ne 0);
=(QInvR0(i) ne 0) and (QInvM0(i) ne 0);
PARAMETER SAM1 SOCIAL ACOUNTING MATRIX -BASE YEAR PRICES-;
SAM1(I,"PK")=PK0(I);
SAM1(ag,"PT")=PT0(ag);
SAM1(I,"PE0")=PE0(I);
SAM1(I,"PM0")=PM0(I);
SAM1(I,"PR0")=PR0(I);
SAM1(I,"P0")=P0(I);
SAM1(I,"PR0")=PR0(I);
PARAMETER SAM2 SOCIAL ACCOUNTING MATRIX -BASE YEAR DATA-;
SAM2(I,"L0")=L0(I);
SAM2(I,"K0")=K0(I);
SAM2(I,"KS0")=KS0(I);
SAM2(I,"T0")=T0(I);
SAM2(I,"TS0")=TS0(I);
SAM2(I,"VA0")=VA0(I);
SAM2(I,"TVR0")=TVR0(I);
SAM2(I,"TVM0")=TVM0(I);
SAM2(I,"TV0")=TV0(I);
SAM2(I,"IBT0")=IBT0(I);
SAM2(I,"X0")=X0(I);
SAM2(I,"M0")=M0(I);
SAM2(I,"R0")=R0(I);
SAM2(I,"E0")=E0(I);
SAM2(I,"Q0")=Q0(I);
SAM2(I,"QR0")=QR0(I);
SAM2(I,"QM0")=QM0(I);
SAM2(I,"QGOV0")=QGOV0(I);
SAM2(I,"QGOVR0")=QGOVR0(I);
SAM2(I,"QGOVM0")=QGOVM0(I);
SAM2(I,"QINV0")=QINV0(I);
SAM2(I,"QINVR0")=QINVR0(I);
SAM2(I,"QINVM0")=QINVM0(I);
OPTION DECIMALS=0;
DISPLAY SAM1;
OPTION DECIMALS=3;
DISPLAY SAM2;
DISPLAY V0,VM0,VR0,LS0,PL0, PLROC0,LHHH0,LGOV0,LY0,KY0,TY0,
YENT0,REMIT0,YH0,DYH0,YGOV0,GRP0,HSAV0,HEXP0,GOVEXP0,SAV0,ROWSAV0,
TRGOV0,ENTY0,ENTTAX0,GOVBOR0;
*##########################################################*
*
*
*
PARAMETER CALIBRATION
*
*
*
*##########################################################*
*#####-- CALIBRATION
*@Production block
a0(i)
a(j,i)
alpha(ag,"K")
alpha(ag,"T")
alpha(ag,"L")
alpha(nag,"K")
alpha(nag,"L")
Ava(ag)
Ava(nag)
RHOv(i)
=VA0(i)/X0(i);
=V0(j,i)/X0(i);
=VAD(ag,"K")/VA0(ag);
=VAD(ag,"T")/VA0(ag);
=1-alpha(ag,"K")-alpha(ag,"T");
=VAD(nag,"K")/VA0(nag);
=1-alpha(nag,"K");
=VA0(ag)/Prod(f,VAD(ag,f)**alpha(ag,f));
=VA0(nag)/PROD(fl,VAD(nag,fl)**alpha(nag,fl));
=1-1/ParamA("SIGMAv",i);
deltav1(j,i)
$(NZV(j,i))
deltav(j,i)
$(NZV(j,i))
Av(j,i)
$(NZV(j,i))
RHOx(i)
deltax1(i)
deltax(i)
Ax(i)
=(VR0(j,i)/VM0(j,i))**(1-RHOv(j))*(PR0(j)/PM0(j));
=1/(1+deltav1(j,i));
=V0(j,i)/(deltav(j,i)*VM0(j,i)**RHOv(j)
+(1-deltav(j,i))
*VR0(j,i)**RHOv(j))**(1/RHOv(j));
=1+1/ParamA("SIGMAx",i);
=(R0(i)/E0(i))**(1-RHOx(i))*(PR0(i)/PE0(i));
=1/(1+deltax1(i));
=X0(i)/(deltax(i)*E0(i)**RHOx(i)+(1-deltax(i))
*R0(i)**RHOx(i))**(1/RHOx(i));
*@Income block
sstax
=ParamB("L","FTAX0")/LY0;
ktax
=ParamB("K","FTAX0")/KY0;
ttax
=ParamB("T","FTAX0")/TY0;
retr
=ParamB("K","RETENT0")/sum(i,VAD(i,"K"));
ibtax(i)
=ParamA("IBT0",i)/(PR0(i)*X0(i));
et
=ENTTAX0/KY0;
hhtax
=ParamC("HOUSE","HTAX0")/YH0 ;
ltr
=1;
mps
=ParamC("HOUSE","HSAV0")/YH0 ;
*@Expenditure block
RHOq(i) = 1-1/ParamA("SIGMAq",i);
deltaq1(i)$NZQ(i) = (QR0(i)/QM0(i))**(1-RHOq(i))*(PR0(i)/PM0(i));
deltaq(i)$NZQ(i) =1/(1+deltaq1(i));
Aq(i)$NzQ(i) = Q0(i)/(deltaq(i)*QM0(i)**RHOq(i)+(1deltaq(i))*QR0(i)**RHOq(i))**(1/RHOq(i));
RHOgov(i) = 1-1/ParamA("SIGMAgov",i);
deltagov1(i)$NZGOV(i) =(QGOVR0(i)/QGOVM0(i))**(1-RHOgov(i))*(PR0(i)/PM0(i));
deltagov(i)$NZGOV(i) = 1/(1+deltagov1(i));
Agov(i)$NZGOV(i) = QGOV0(i)/(deltagov(i)*QGOVM0(i)**RHOgov(i)+(1deltagov(i))*QGOVR0(i)**RHOgov(i))**(1/RHOgov(i));
RHOinv(i)= 1-1/ParamA("SIGMAinv",i);
deltainv1(i)$NZInv(i) = (QINVR0(i)/QINVM0(i))**(1-RHOinv(i))*(PR0(i)/PM0(i));
deltainv(i)$NZInv(i) = 1/(1+deltainv1(i));
Ainv(i)$NZInv(i) = QINV0(i)/(deltainv(i)*QINVM0(i)**RHOinv(i)+(1deltainv(i))*QINVR0(i)**RHOinv(i))**(1/RHOinv(i));
beta(i) = Q0(i)*P0(i)/HEXP0;
PARAMETER CALIBR PARAMETER CALIBRATED;
CALIBR(I,"A0")=A0(I);
CALIBR(I,"AVA")=AVA(I);
CALIBR(I,"RHOV")=RHOv(I);
CALIBR(I,"RHOQ")=RHOQ(I);
CALIBR(I,"DELTAQ")=DELTAQ(I);
CALIBR(I,"AQ")=AQ(I);
CALIBR(I,"IBTAX")=IBTAX(I);
CALIBR(I,"RHOGOV")=RHOGOV(I);
CALIBR(I,"DELTAGOV")=DELTAGOV(I);
CALIBR(I,"AGOV")=AGOV(I);
CALIBR(I,"RHOINV")=RHOINV(I);
CALIBR(I,"AINV")=AINV(i);
CALIBR(I,"RHOX")=RHOX(i);
CALIBR(I,"DELTAX")=DELTAX(i);
CALIBR(I,"AX")=AX(i);
CALIBR(I,"BETA")=BETA(i);
DISPLAY CALIBR;
DISPLAY a,Av,deltav,alpha,
ktax,sstax,ttax,retr,et,mps,hhtax;
*##########################################################*
*
*
*
VARIABLE DECLARATION
*
*
*
*##########################################################*
* ENDOGENOUS VARIABLES
VARIABLES
Z
Objective Function Value
*@Price block
PL
PK(i)
PKL
PT(ag)
PN(i)
PR(i)
P(i)
PX(i)
Wage rate
Capital rate
Capital rate in the long run
Land rent
Net price
Regional price
Composite price
Composite price faced by consumers
*@Production block
LAB(i)
CAP(i)
LAND(ag)
TCAP
TLAB
LS
LMIG
KMIG
VA(i)
V(j,i)
VM(j,i)
VR(j,i)
R(i)
X(i)
EXP(i)
M(i)
TVM(i)
TVR(i)
TV(i)
adjL
Labor demand
Capital demand
Land demand
Total Capital Demand
Total Labor Demand
Labor supply
Labor migration
Capital migration
Value added
Composite intermediate good demand
Imported int good demand
Reg int good demand
Regional supply
Output
Export
Import
Imported int good total demand
Reg int good total demand
Composite intermediate good total demand
Labor adjustment
*@Income block
LY
ALY
KY
TY
YENT
Labor income (original hhs)
Adjusted labor income (staying + in-migrating)
capital income (original capital stock)
Land income
Enterprise income
RETENT
YH
DYH
HSAV
SAV
INV
YGOV
IBTX
GRP
Retained Earnings by enterprises
Income of hh staying in the region (including in-migrants)
Disposable hh income (staying in the region + inmigra)
Household saving (staying +inmigrat)
Total saving
Investment
gov revenue
Indirect business tax
Gross region product
*### Expenditure block
AHEXP
Adjusted household expenditure (spent within the region)
Q(i)
Demand for comp consump good
QM(i)
Demand for imp consump good
QR(i)
Demand for reg consump good
GOVEXP
gov expend
QGOV(i)
gov demand for comp good
QGOVM(i)
gov demand for imported good
QGOVR(i)
gov demand for reg good
QINV(i)
Invest gov demand for comp good
QINVM(i)
Invest gov demand for imported good
QINVR(i)
Invest gov demand for reg good
SLACK(i)
SLACK2(i)
POSITIVE VARIABLE
SLACK, SLACK2;
*##########################################################*
*
*
*
EQUATION DECLARATION
*
*
*
*##########################################################*
*This section declares the equations of the model
*which are those presented in table 5.1
EQUATIONS
EQZ
*@Price block
NETprice(i)
Price(i)
Price1(i)
objective function
net price
composite price
*@Production block
Ldemand(i)
labor demand
KdemandSR(i)
capital demand
KdemandLR(i)
Tdemand(ag)
land demand
TLdem
total labor demand
TKdem
total capital demand
VAdemand(i)
value added demand
Vdemand(j,i)
intermediate demand
VAprod1(nag)
value added prod fc
VAprod2(ag)
value added prod fc
Vces(j,i)
ces fc for int demand
TVdemand(i)
intermediate total demand
TVRdemand(i)
TVMdemand(i)
VRdem(j,i)
VRdem0(j,i)
VMDem0(j,i)
Xcet(i)
Rsupply(i)
LSupply
LMIGrat
adjustL
KMIGrat
KMIGrat1
*@Income block
LYincome
ALYincome
KYincomeSR
KYincomeLR
TYincome
YENTincome
RETearn
YHincome
DHYincome
HSAVings
SAVings
INVest
YGOVincome
INDtax
GRProduct
int reg total demand
int imp total demand
demand for reg int good
demand for reg int good for goods with zero import
demand for imp int good for goods with zero import
cet fc for reg product
reg supply of reg product
labor supply
labor migration
labor migration adjustment
capital migration
labor income
adjusted labor income
capital income
land income
enterprise income
Retained earning by enterprises
household income
disposable income
household savings
total savings
total investment
Government income
Indirect business tax
gross region product
*@Expenditure block
AHEXPLow
adj. household expenditure
Qces
ces fc for consumption
Qdemand
cons demand for composite good
QRdem0
cons demand for reg goods
QRdem1
QRdem2
QMdem1
QMdem2
GOVEXPend
Gov expenditure
QGOVces
ces for st and loc gov demand
QGOVdemand
st and loc gov cons
QGOVRdem0
st and loc gov reg cons
QGOVRDem1
QGOVRDem2
QGOVMDem1
QGOVMDem2
QINVces
ces for invest gov demand
QINVemand
invest gov cons
QINVRdem0
invest gov reg cons
QInvRdem1
QInvRdem2
QInvMdem1
QInvMdem2
Mimports(i)
import
*@Equilibrium
COMMequil(i)
Lequil
Kequil(i)
Kequil1
Tequil(ag)
comm market equilibrium
labor market equilibrium
cap market equilibrium
land market equilibrium;
*##########################################################*
*
*
*
EQUATION DEFINITION
*
*
*
*##########################################################*
*All equations are defined following the algebraic structure
*on table 5.1.
EQZ..
*@Price block
NETprice(i)..
Price(i)..
Price1(i)..
Z
PN(i)
P(i)
PX(i)
=e= sum(i,SLACK(i)+SLACK2(i));
=e= PX(i)-sum(j,A(j,i)*P(j))-ibtax(i)*PX(i);
=e= (PR(i)*R(i)+PM0(i)*M(i))/(R(i)+M(i));
=e= (PR(i)*R(i)+PE0(i)*Exp(i))/(R(i)+Exp(i));
*@Production block
Ldemand(i)..
LAB(i) =e= alpha(i,"L") *PN(i)*X(i)/PL;
KdemandSR(i)$(Not Kmobil)..
CAP(i) =e= alpha(i,"K")*PN(i)*X(i)/PK(i);
KdemandLR(i)$(Kmobil)..
CAP(i) =e= alpha(i,"K")*PN(i)*X(i)/PKL;
Tdemand(ag)..
LAND(ag)=e= alpha(ag,"T") *PN(ag)*X(ag)/PT(ag);
TLdem..
TLAB =e= Sum(i,LAB(i));
TKdem..
TCAP =e= Sum(i,CAP(i));
LSupply ..
LS
=e= LS0;
LMIGrat ..
LMIG =e= etaL*LS0*LOG(PL/PLROC0);
adjustL..
adjL =e= (LS0+LMIg)/LS0;
KMIGrat$(KMobil).. KMIG =e=etaK*(SUM(i,K0(i))*LOG(PKL/PKROC0));
KMIGrat1$(not KMobil).. KMIG
=e= 0;
VAdemand(i)..
VA(i)+SLACK(i)+SLACK2(i)=e= a0(i)*X(i);
VAprod1(nag).. VA(nag) =e= Ava(nag)*LAB(nag)**alpha(nag,"L")*CAP(nag)**
alpha(nag,"K");
VAprod2(ag)..
VA(ag)
=e= Ava(ag)*LAB(ag)**alpha(ag,"L")*CAP(ag)**
alpha(ag,"K")*LAND(ag)**alpha(ag,"T");
Vdemand(j,i)..
V(j,i) =e= a(j,i)*X(i);
Vces(j,i)..
V(j,i) =e= Av(j,i)*(deltav(j,i)*VM(j,i)
**RHOv(j)+(1-deltav(j,i))
*VR(j,i)**RHOv(j))**(1/RHOv(j));
TVdemand(i)..
TV(i)
=e= sum(j,V(i,j));
VRdem(j,i)$NZV(j,i)..
VR(j,i) =e= VM(j,i)*((1-deltav(j,i))/
deltav(j,i)*
PM0(j)/PR(j))**(1/(1-RHOv(j)));
VRdem0(j,i)$ZVM(j,i)..
VR(j,i) =e= V(j,i);
VMdem0(j,i)$ZVM(j,i)..
VM(j,i) =e= 0;
TVRdemand(i)..
TVR(i) =e= sum(j,VR(i,j));
TVMdemand(i)..
TVM(i) =e= sum(j,VM(i,j));
Xcet(i)..
X(i)
=e= Ax(i)*(deltax(i)*EXP(i)**RHOx(i)+(1deltax(i))*R(i)**RHOx(i))
**(1/RHOx(i));
Rsupply(i)..
R(i)
=e= EXP(i)*((1-DELTAx(i))/DELTAx(i)
INDtax..
GRProduct..
IBTX
GRP
*PE0(i)/PR(i))**(1/(1-RHOx(i)));
=E= Sum(i,ibtax(i)*X(i));
=e= ALY + KY + TY + IBTX;
*@Income block
*ALY is defined for all labor; LY is defined for original household
ALYincome..
ALY
=e= PL*(TLAB+LHHH0+LGOV0);
LYincome..
LY
=e= ALY+PLROC0*(SQRT(LMig**2)-LMig)*0.5
-PL*(SQRT(LMig**2)+LMig)*0.5;
KYincomeSR$(not kmobil)..
KY
=e= sum(i,PK(i)*CAP(i));
KYincomeLR$(kmobil)..
KY
=e= sum(i,PKL*CAP(i))+PKROC0*(SQRT(KMIG**2)-KMIG)
*0.5-PKL*(SQRT(KMIG**2)+KMIG)*0.5;
RETearn..
RETENT =e= retr*KY;
TYincome..
TY
=e= sum(ag,PT(ag)*LAND(ag));
YENTincome..
YENT
=e= KY*(1-ktax);
YHincome ..
YH
=e= ALY*(1-sstax)
+TY*(1-ttax)+(YENT-RETENT-et*KY)
+REMIT0+adjL*TRGOV0
-((SQRT((adjL-1)**2)-(adjL-1))*0.5)
*(TY*(1-ttax)+(YENT-RETENT-et*KY)
+REMIT0);
DHYincome ..
DYH
=e= YH *(1-hhtax );
HSAVings ..
HSAV =e= mps *YH ;
SAVings..
SAV
=e= HSAV+RETENT+ROWSAV0;
INVest..
INV
=e= sum(i,P(i)*QINV(i));
YGOVincome..
YGOV
=e= Sum(i,ibtax(i)*PX(i)*X(i))
+sstax*ALY
+ktax*KY+et*KY
+ttax*TY
+hhtax *YH+GOVBOR0+GOVITR0;
*@Expenditure block
AHEXPLow..
AHEXP =e= DYH-HSAV-PL*LHHH0;
Qdemand(i).. Q(i)
=e= beta(i)*AHEXP/P(i);
Qces(i)$NZQ(i).. Q(i) =e= Aq(i)*(deltaq(i)*QM(i)
**RHOq(i)+(1-deltaq(i))*QR(i)**RHOq(i))
**(1/RHOq(i));
QRdem0(i)$NZQ(i).. QR(i) =e= QM(i)*((1-deltaq(i))/deltaq(i)
*PM0(i)/PR(i))**(1/(1-RHOq(i)));
QRdem1(i)$ZQM(i).. QM(i) =e= 0;
QMdem1(i)$ZQM(i).. QR(i) =e= Q(i);
QRdem2(i)$ZQR(i).. QR(i) =e= 0;
QMdem2(i)$ZQR(i).. QM(i) =e= Q(i);
GOVEXPend..
GOVEXP
=e= sum(i,P(i)*QGOV(i))+adjL*
TRGOV0+PL*LGOV0+GOVITR0;
QGOVdemand(i)..
QGOV(i)
=e= QGOV0(i);
QGOVces(i)$NZGOV(i)..
QGOV(i) =e= Agov(i)*(deltagov(i)
*QGOVM(i)**RHOgov(i)+(1-deltagov(i))
*QGOVR(i)**RHOgov(i))**(1/RHOgov(i));
QGOVRdem0(i)$NZGOV(i)..
QGOVR(i) =e=QGOVM(i)*((1-deltagov(i))
/deltagov(i)*PM0(i)/PR(i))**(1/(1-RHOgov(i)));
QGOVRdem1(i)$ZGOVM(i)..
QGOVM(i) =e= 0;
QGOVMdem1(i)$ZGOVM(i)..
QGOVR(i) =e= QGOV(i);
QGOVRdem2(i)$ZGOVR(i)..
QGOVR(i) =e= 0;
QGOVMdem2(i)$ZGOVR(i)..
QGOVM(i) =e= QGOV(i);
QINVemand(i)..
QINV(i) =e= QINV0(i);
QINVces(i)$NZInv(i)..
QINV(i) =e=Ainv(i)*(deltainv(i)*QINVM(i)
**RHOinv(i)+(1deltainv(i))*QINVR(i)**RHOinv(i))
**(1/RHOinv(i));
QINVRdem0(i)$NZInv(i).. QINVR(i)=e= QINVM(i)*((1-deltainv(i))
/deltainv(i)*PM0(i)/PR(i))**(1/(1-RHOinv(i)));
QInvRDem1(i)$ZInvM(i).. QInvM(i)=e= 0;
QInvMDem1(i)$ZInvM(i).. QInvR(i)=e= QInv(i);
QInvRDem2(i)$ZInvR(i).. QInvR(i)=e= 0;
QInvMDem2(i)$ZInvR(i).. QInvM(i)=e= QInv(i);
Mimports(i)..
M(i)
=e= TVM(i)+QM(i)+QGOVM(i)+QINVM(i);
*@Equilibrium
COMMequil(i).. X(i)+M(i)=e=TV(i)+Q(i)+QGOV(i)+QINV(i)+EXP(i);
Lequil..
sum(i,LAB(i))+LHHH0+LGOV0 =e= LS0+LMIG;
Kequil1$(KMobil)..
KMig =e= Sum(i,CAP(i)-KS0(i));
Kequil(i)$(not KMobil).. CAP(i)
=e= KS0(i);
Tequil(ag)..
LAND(ag) =e= T0(ag);
*##########################################################*
*
*
*
INITIALIZATION OR STARTING VALUES
*
*
*
*##########################################################*
*@Price block
*@Income block
PL.L
=PL0
;
PKL.L
=1;
PK.L(i)
=PK0(i)
;
PT.L(ag)
=PT0(ag)
;
HSAV.L
=HSAV0
;
PR.L(i)
=PR0(i)
;
YGOV.L
=YGOV0
;
P.L(i)
=P0(i)
;
PX.L(i)
= PX0(i)
;
PN.L(i)
= PX0(i)-sum(j,A(j,i)*P0(j))-ibtax(i)*PX0(i);
*@Production block
SLACK.L(i) =0;
LAB.L(i) =L0(i)
;
CAP.L(i) =K0(i)
;
*
LAND.L(ag) =T0(ag)
;
SLACK2.L(i)
=0;
INV.L
=INV0;
GRP.L
=GRP0;
*@Expenditure block
LS.L
= LS0;
LMIG.L
=0;
KMIG.L
=0;
VA.L(i)
=VA0(i)
;
VM.L(j,i) =VM0(j,i) ;
VR.L(j,i) =VR0(j,i) ;
QM.L(i) =QM0(i)
;
V.L(j,i)
=V0(j,i)
;
TVM.L(i)
=TVM0(i)
;
TVR.L(i)
=TVR0(i)
;
GOVEXP.L
=GOVEXP0
;
TV.L(i)
=TV0(i)
;
QGOV.L(i) =QGOV0(i)
;
R.L(i)
=R0(i)
;
QGOVM.L(i) =QGOVM0(i)
;
X.L(i)
=X0(i)
;
QGOVR.L(i) =QGOVR0(i)
;
EXP.L(i) =E0(i)
;
M.L(i)
=M0(i)
;
Q.L(i)
=beta(i)*HEXP0/PX0(i);
QR.L(i) =QR0(i)
;
*@Income block
LY.L
=LY0
KY.L
=KY0
TY.L
=TY0
adjL.L
=1
;
YENT.L
=YENT0
YH.L
=YH0
;
SAV.L
=SAV0
DYH.L
=DYH0
;
QINVM.L(i) =QINVM0(i)
QINVR.L(i) =QINVR0(i)
QINV.L(i) =QINV0(i)
;
;
;
;
;
;
;
;
*##########################################################*
*
*
*
VARIABLE BOUNDS
*
*
*
*##########################################################*
PL.LO
= 0.000001;
PT.LO(ag)
= 0.000001;
PK.LO(i)
= 0.000001;
PR.LO(i)
= 0.000001;
PN.LO(i)
= 0.000001;
P.LO(i)
= 0.000001;
R.LO(i)
= 0.000001;
PX.LO(i)
= 0.000001;
QM.LO(i)$(QM0(i) ne 0) = 0.000001;
QR.LO(i)$(QR0(i) ne 0) = 0.000001;
Q.LO(i)$(Q0(i) ne 0)
= 0.000001;
QM.LO(i)$(QM0(i) eq 0) = 0;
QR.LO(i)$(QR0(i) eq 0) = 0;
Q.LO(i)$(Q0(i) eq 0)
= 0;
VR.LO(i,j)$(VR0(i,j) ne 0) = 0.000001;
VM.LO(i,j)$(VM0(i,j) ne 0) = 0.000001;
V.LO(i,j)$(V0(i,j) ne 0)
= 0.000001;
VR.LO(i,j)$(VR0(i,j) eq 0) = 0;
VM.LO(i,j)$(VM0(i,j) eq 0) = 0;
V.LO(i,j)$(V0(i,j) eq 0)
= 0;
OPTIONS ITERLIM=5000, LIMROW=0, LIMCOL=0, SOLPRINT=OFF;
*-- MODEL DEFINITION AND SOLVE STATEMENT
MODEL OKLAHOMA /ALL/;
SOLVE OKLAHOMA MINIMIZING Z USING NLP;
*-- SOLUTION DISPLAY STATEMENT
*-- SOLUTION VALUES OF ENDOGENOUS VARIABLES
PARAMETER VALID VARIABLES FOR THE VALIDATION OF THE MODEL;
VALID(i,"SLACK1") = SLACK.L(i);
VALID(i,"SLACK2") = SLACK2.L(i);
VALID(i,"PR") = PR.L(i);
VALID(i,"P") = P.L(i);
VALID(i,"PN") = PN.L(i);
VALID(i,"PK") = PK.L(i);
VALID(ag,"PT") = PT.L(ag);
VALID(i,"PX") = PX.L(i);
VALID(i,"PE") = PE0(i);
VALID(i,"X") = X.L(i);
VALID(i,"R") = R.L(i);
VALID(i,"EXP") =EXP.L(i);
VALID(i,"M") = M.L(i);
VALID(i,"VA") = VA.L(i);
VALID(i,"LAB") =LAB.L(i);
VALID(i,"CAP") =CAP.L(i);
VALID(ag,"LAND") =LAND.L(ag);
VALID(i,"TVR") =TVR.L(i);
VALID(i,"TVM") =TVM.L(i);
VALID(i,"TV") =TV.L(i);
VALID(i,"Q") =Q.L(i);
VALID(i,"QR") =QR.L(i);
VALID(i,"QM") =QM.L(i);
VALID(i,"QGOV") =QGOV.L(i);
VALID(i,"QGOVR") =QGOVR.L(i);
VALID(i,"QGOVM") =QGOVM.L(i);
VALID(i,"QINV") =QINV.L(i);
VALID(i,"QINVR") =QINVR.L(i);
VALID(i,"QINVM") =QINVM.L(i);
PARAMETER VALID2 -INTERMEDIATE USE MATRIX-;
VALID2(I,"AGR","V")=V.L(I,"AGR");
VALID2(I,"MIN","V")=V.L(I,"MIN");
VALID2(I,"MAN","V")=V.L(I,"MAN");
VALID2(I,"SER","V")=V.L(I,"SER");
VALID2(I,"AGR","VR")=VR.L(I,"AGR");
VALID2(I,"MIN","VR")=VR.L(I,"MIN");
VALID2(I,"MAN","VR")=VR.L(I,"MAN");
VALID2(I,"SER","VR")=VR.L(I,"SER");
VALID2(I,"AGR","VM")=VM.L(I,"AGR");
VALID2(I,"MIN","VM")=VM.L(I,"MIN");
VALID2(I,"MAN","VM")=VM.L(I,"MAN");
VALID2(I,"SER","VM")=VM.L(I,"SER");
PARAMETER VALID3 -VALIDATION OF THE MODEL-;
VALID3("OBJECTIVE") = Z.L;
VALID3("PL") = PL.L;
VALID3("LMIG")=LMIG.L;
VALID3("KMIG")=KMIG.L;
VALID3("TCAP")=TCAP.L;
VALID3("TLAB")=TLAB.L;
VALID3("LS")=LS.L;
VALID3("LMIG")=LMIG.L;
VALID3("ADJL") = ADJL.L;
VALID3("LY")=LY.L;
VALID3("ALY")=ALY.L;
VALID3("KY")=KY.L;
VALID3("TY")=TY.L;
VALID3("YENT") = YENT.L;
VALID3("RETENT")=RETENT.L;
VALID3("YH")=YH.L;
VALID3("PL") = PL.L;
VALID3("DYH")=DYH.L;
VALID3("HSAV")=HSAV.L;
VALID3("SAV")=SAV.L;
VALID3("INV") = INV.L;
VALID3("YGOV")=YGOV.L;
VALID3("GOVEXP")=GOVEXP.L;
VALID3("IBTX")=IBTX.L;
VALID3("GRP")=GRP.L;
VALID3("AHEMP")=AHEXP.L;
option decimals=3;
DISPLAY VALID,VALID2,VALID3;
*######## SIMULATION ############*
PE0(i)=1.1;
model simul1 /all/;
solve simul1 minimizing z using nlp;
OPTION SOLPRINT=OFF;
*-- SOLUTION DISPLAY STATEMENT
*-- SOLUTION VALUES OF ENDOGENOUS VARIABLES
PARAMETER PRICES MARKET CLEARING PRICES;
PRICES(i,"SLACK1") = SLACK.L(i);
PRICES(i,"SLACK2") = SLACK2.L(i);
PRICES(i,"PR") = PR.L(i);
PRICES(i,"P") = P.L(i);
PRICES(i,"PN") = PN.L(i);
PRICES(i,"PK") = PK.L(i);
PRICES(ag,"PT") = PT.L(ag);
PRICES(i,"PX") = PX.L(i);
PRICES(i,"PE") = PE0(i);
PARAMETER PROD1 MARKET CLEARING PRODUCTION VARIABLES;
PROD1(i,"X") = X.L(i);
PROD1(i,"R") = R.L(i);
PROD1(i,"EXP") =EXP.L(i);
PROD1(i,"M") = M.L(i);
PROD1(i,"VA") = VA.L(i);
PROD1(i,"LAB") =LAB.L(i);
PROD1(i,"CAP") =CAP.L(i);
PROD1(ag,"LAND") =LAND.L(ag);
PARAMETER TRADE1 MARKET CLEARING PRODUCTION VARIABLES;
TRADE1(i,"TVR") =TVR.L(i);
TRADE1(i,"TVM") =TVM.L(i);
TRADE1(i,"TV") =TV.L(i);
TRADE1(i,"Q") =Q.L(i);
TRADE1(i,"QR") =QR.L(i);
TRADE1(i,"QM") =QM.L(i);
TRADE1(i,"QGOV") =QGOV.L(i);
TRADE1(i,"QGOVR") =QGOVR.L(i);
TRADE1(i,"QGOVM") =QGOVM.L(i);
TRADE1(i,"QINV") =QINV.L(i);
TRADE1(i,"QINVR") =QINVR.L(i);
TRADE1(i,"QINVM") =QINVM.L(i);
PARAMETER PRODUCT2 -PRODUCTION SYSTEMS VARIABLES-;
PRODUCT2(I,"AGR","V")=V.L(I,"AGR");
PRODUCT2(I,"MIN","V")=V.L(I,"MIN");
PRODUCT2(I,"MAN","V")=V.L(I,"MAN");
PRODUCT2(I,"SER","V")=V.L(I,"SER");
PRODUCT2(I,"AGR","VR")=VR.L(I,"AGR");
PRODUCT2(I,"MIN","VR")=VR.L(I,"MIN");
PRODUCT2(I,"MAN","VR")=VR.L(I,"MAN");
PRODUCT2(I,"SER","VR")=VR.L(I,"SER");
PRODUCT2(I,"AGR","VM")=VM.L(I,"AGR");
PRODUCT2(I,"MIN","VM")=VM.L(I,"MIN");
PRODUCT2(I,"MAN","VM")=VM.L(I,"MAN");
PRODUCT2(I,"SER","VM")=VM.L(I,"SER");
PARAMETER OTHER1 MARKET CLEARING VALEUES OF VARIABLES;
OTHER1("OBJECTIVE") = Z.L;
OTHER1("PL") = PL.L;
OTHER1("LMIG")=LMIG.L;
OTHER1("KMIG")=KMIG.L;
OTHER1("TCAP")=TCAP.L;
OTHER1("TLAB")=TLAB.L;
OTHER1("LS")=LS.L;
OTHER1("LMIG")=LMIG.L;
OTHER1("ADJL") = ADJL.L;
OTHER1("LY")=LY.L;
OTHER1("ALY")=ALY.L;
OTHER1("KY")=KY.L;
OTHER1("TY")=TY.L;
OTHER1("YENT") = YENT.L;
OTHER1("RETENT")=RETENT.L;
OTHER1("YH")=YH.L;
OTHER1("PL") = PL.L;
OTHER1("DYH")=DYH.L;
OTHER1("HSAV")=HSAV.L;
OTHER1("SAV")=SAV.L;
OTHER1("INV") = INV.L;
OTHER1("YGOV")=YGOV.L;
OTHER1("GOVEXP")=GOVEXP.L;
OTHER1("IBTX")=IBTX.L;
OTHER1("GRP")=GRP.L;
OTHER1("AHEMP")=AHEXP.L;
option decimals=3;
DISPLAY PROD1, TRADE1,PRODUCT2;
OPTION DECIMALS = 8;
DISPLAY OTHER1, PRICES;
* Parameters AS INDEX WITH 1993=1.000
PARAMETERS
* -- Price block
IPL
Wage rate index
IPK(i)
Rent to capital index
IPT(ag)
Land rent index
IPR(i)
Regional price index
IP(i)
Composite price index
IPG
General composite price index
* -- Production block
IL(i)
Labor demand index
ITL
Total labor demand index
ILS
Labor supply index
IK(i)
capital demand index
ITK
Total Capital use index
ITT
Total Land use index
IT(ag)
Land demand index
IVA(i)
Value added index
IX(i)
Output index
ITVA
Total Value added index
ITX
Total Output index
ITE
Total Export index
ITR
Total Reg. supply index
ITM
Total Import index
IVM(j,i)
Imported interm demand index
IVR(j,i)
Regional interm demand index
IR(i)
Regional supply index
IE(i)
Export index
IM(i)
Import index
* -- Income block
IYH
Household (in the region) income index
YHch
Change in hh income
IDYH
Disposable income index
IHSAV
Household saving index
IYGOV
Government revenue index
NETGOV
Net Revenue for government
IGRP
Gross region product index
GRPch
Change in Gross regional product
CapComp
Capital Compensation
LandComp
Land Compensation
Rconsup
Resident angler consumer surplus loss
NRconsup
NonResident angler consumer surplus loss
* -- Expenditure block
IAHEXP
adj. Household expenditure index
IGOVEXP
Government expenditure index
IQ(i)
Commodity demand index
IQM(i)
Imported commodity demand index
IQR(i)
Regional commodity demand index
;
*-- EQUATIONS FOR CALCULATION OF INDEX WITH 1993=1.000
*### Price block
IPL
= PL.L/PL0;
IPK(i)
= PK.L(i)/PK0(i);
IPT(ag) = PT.L(ag)/PT0(ag);
IPR(i)
= PR.L(i)/PR0(i);
IP(i)
= P.L(i)/P0(i);
IPG
=SUM(i, (PR.L(i)*R0(i)+PM0(i)*M0(i))/(R0(i)+M0(i)))/4;
*#* Production block
IL(i)
= LAB.L(i)/L0(i);
ITL
= (Sum(i,LAB.L(i))+(LHHH0+LGOV0))
/(Sum(i,L0(i))+LHHH0+LGOV0);
ILS
= LS.L /LS0 ;
IK(i)
= CAP.L(i)/K0(i);
ITK
= Sum(i,PK.L(i)*CAP.L(i))/Sum(i,K0(i));
IT("Agr") = LAND.L("Agr")/T0("Agr");
ITT
= PT.L("Agr")*LAND.L("Agr")/T0("Agr");
IVA(i)
= VA.L(i)/Va0(i);
ITVA
= Sum(i,VA.L(i))/Sum(i,Va0(i));
IX(i)
= X.L(i)/X0(i);
ITX
=Sum(i,X.L(i))/Sum(i,X0(i));
ITR
=Sum(i,R.L(i))/Sum(i,R0(i));
ITM
=Sum(i,M.L(i))/Sum(i,M0(i));
IVM(j,i)= VM.L(j,i)/VM0(j,i);
IVR(j,i)= VR.L(j,i)/VR0(j,i);
IR(i)
= R.L(i)/R0(i);
IE(i)
= EXP.L(i)/E0(i);
ITE
=Sum(i,EXP.L(i))/Sum(i,E0(i));
*## Income block
IYH
= YH.L /YH0 ;
IDYH
= DYH.L /DYH0 ;
IHSAV
= HSAV.L /HSAV0 ;
IGRP
= GRP.L/GRP0;
GRPch
= GRP.L-GRP0;
*#Expenditure block
IAHEXP
= AHEXP.L /HEXP0 ;
IQ(i)
= Q.L(i)/Q0(i);
IQM(i)
= QM.L(i)/QM0(i);
IQR(i)
= QR.L(i)/QR0(i);
IM(i)
= M.L(i)/M0(i);
YHch
= YH.L -adjL.L*YH0 ;
IYGOV
= YGOV.L/YGOV0;
IGOVEXP
= GOVEXP.L/GOVEXP0;
NETGOV
= YGOV.L-GOVEXP.L;
*##- SOLUTION VALUES OF INDEX
option decimals=5;
PARAMETER INDEX INDEXES FOR THE SIMULATION;
INDEX(I,"IPR")=IPR(I);
INDEX(I,"IX")=IX(I);
INDEX(I,"IE")=IE(I);
INDEX(I,"IL")=IL(I);
INDEX(I,"IK")=IK(I);
INDEX(I,"IPK")=IPK(I);
INDEX(ag,"IPT")=IPT(ag);
INDEX(ag,"IT")=IT(ag);
INDEX(I,"IVA")=IVA(I);
INDEX(I,"IR")=IR(I);
INDEX(I,"IM")=IM(I);
INDEX(I,"IQ")=IQ(I);
INDEX(I,"IQR")=IQR(I);
INDEX(I,"IQM")=IQM(I);
INDEX(I,"IPR")=IPR(I);
INDEX(I,"IPR")=IPR(I);
DISPLAY INDEX;
DISPLAY ITX,ITE,ITL,IPL,
ITK,ITT,
IGRP,GRPch,ITVA,ITR,ITM, YHch,
IYH, IYGOV,IGOVEXP,NETGOV,
ILS,IDYH,IHSAV,IAHEXP,
IVM,IVR;
DISPLAY IGRP,IPG,IYH,ITE,ITM;
1
143
Table 4.1
Competitive CGE Model Equations
Equation
0.
Z =
Description
Equations
å ( SLACKi + SLACK 2i )
Objective function
No. of
Equations
1
Endogenous
Variables
Exogenous
Variables
Parameters
Z SLACKi
i
SLACK2i
PRODUCTION SYSTEM
1.
2a.
2b.
3.
LAB =
i
CAPi =
CAPi =
L
α PN X
i
i i
Labor demand
n
LABi PNi PL Xi
αiL
Capital demand SR
n
CAPi PNi PKi Xi
αiK
Capital demand LR
n
CAPI PNi PK Xi
αiK
Land demand
n
LANDag PNag PTag Xag
αiT
PL
K
α i PN i X i
PK i
K
α i PN i X i
LAND ag =
PK
T
α ag PN ag X ag
PTag
4.
VAi = a0i X i
Composite factor demand
n
VAi Xi
a0i
5.
V ji = a ji X i
Intermediate input demand
nx n
Vji Xi
aji
Table 4.1 (Continued)
Equation
6a.
6b.
7.
8.
VA
VA
Description
Equations
=φ
ag
T
K
L
α
α
α
VA
ag
ag
ag
LAND
CAP
LAB
ag
ag
ag
ag
=φ
nag
K
L
α
α
VA
nag
nag
CAP
LAB
nag
nag
nag
TVRi =
1
VAag LABag CAPag LANDag
φagVA αagL αagK αagT
n-1
VAnag LABnag CAPnag
φnagVA αnagL αnagK
nxn
Vji VMji VRji
n
TVi Vij
Regional produced
intermediate input demand
n2
VMji VRji PRj
Total intermediate
regional demand
n
TVRi VRji
Total intermediate
imported demand
n
TVMi VMji
function sector with land
CES for intermediate
input demand
éæ 1 − δ Vji
ç
ji êç
êëè δ Vji
åVR
ji
öæ PM 0 j
֍
֍ PR j
øè
öù
÷ú
÷ú
øû
σ Vj
j
11.
TVM i =
åVM
j
φjiV δjiV ρjV σjV
intermediate demand
j
10.
Parameters
Total composite
ij
VR ji = VM
Exogenous
Variables
Net product production
function sector without land
åV
9.
Endogenous
Variables
Net product production
1
é
ρV
ρV ù ρV
ú
ê
j
j
j ,σv = 1
V = φ V êδ V VM
+ (1 − δ V )VR
ji
ji ji
ji
ji
ji ú
j
1 − ρv
ú
ê
j
û
ë
TVi =
No. of
Equations
ji
PM0j
δjiV σjV
Table 4.1 (Continued)
Equation
12.
13.
Description
Equations
(
)
x
ρx
x ρ
x
x
X i = φ i éδ i EXP i + 1 − δ i R i
i
i
ëê
Ri
éæ 1 − δ ix
= EXPi êç
ç x
ëêè δ i
öæ PE 0 i
֍
֍ PR
øè i
öù
÷÷ ú
ø ûú
1
ù ρix
úû
, σ iX =
No. of
Equations
Endogenous
Variables
Exogenous
Variables
CET for regional
1
ρ iX − 1
φix δix ρix σix
n
Xi EXPi Ri
Regional supply for
regional demand
n
Ri EXPi PRi
Composite household
demand
n
Qi Pi AHEXPi
βi
n
Qi QMi QRi
φ iQ δ iQ ρ iQ σiQ
n
QRi QMi PRi
n
QGOVi
and export markets
−σ ix
Parameters
PE0i
φix δix σix
COMMODITY MARKETS
æ βi
çP
è i
ö
÷
ø
14.
Q i =ç
15.
Q
Q
ρ
ρ
Q
Qé Q
Q i = φ i êδ i QM i i + 1 − δ i QR i i
16.
17.
⋅ AHEXP ÷
ë
QR i
éæ 1 − δ Q
i
= QM i êç
Q
êëçè δ i
QGOVi
= QGOV0 i
(
1
)
ù ρQ
ú i
û
Q
, σi =
1
Q
1 − ρi
CES for
household demand
1
öæ PM 0 i
֍
÷çè PR i
ø
öù 1− ρiQ
÷÷ú
øúû
Regionally produced
household demand
State / Local gov
commodity demand
PM0j
QGOV0 i
δiQ ρiQ
Table 4.1 (Continued)
Equation
Description
Equations
GOV
∗
QGOVi = φ i
18.
No. of
Equations
CES for government
1
æ GOV
ρ GOV æ
ρ GOV
ö
çδ
+ ç1 − δ GOV ÷ ⋅ QGOVR i
QGOVM i
i
i
i
i
ç
è
ø
è
ö ρ GOV
÷ i
÷
ø
Endogenous
Variables
Exogenous
Variables
φiGOV δiGOV
ρiGOV σiGOV
n
QGOV i
QGOVM i
QGOVR i
State / Local government
demand for regional good
n
QGOVRi
QGOVM i PRi
PM0i
Investment demand
n
QINVi
QINV0i
n
QINVi QINVMi
QINVRi
n
QINVR i
domestic and import
demand
Parameters
1
19.
QGOVRi
éæç 1 − δ GOV
i
= QGOVM i êç
êçç δ GOV
ëè i
ö æ
÷ ç PM 0
i
÷⋅ç
÷ ç PR
÷ è
i
ø
20.
QINVi = QINV 0i
21.
ρiINV
INV é INV
QINVi = φ i
êδ i QINVM i
ö ù 1 − ρ GOV
÷ú
i
÷
÷ú
ø
û
CES for investment
domestic and import
ë
(
)
INV
ρi
INV
+ 1− δ i
⋅ QINVR i
δ GOV
i
ρGOV
i
φiINV δiINV
ρiINV σiINV
demand
ù
úû
1
ρ INV
i
1
22.
QINVR i
éæ 1 - δ INV ö æ PM0 öù 1− ρiINV
ç i ÷⋅ç
i ÷ú
= QINVM i ê
êçç δ INV ÷÷ çè PR i ÷øú
ø
ëè i
û
Investment demand
for regional good
QINVMi PR i
PM0i
δiINV ρiINV
Table 4.1 (Continued)
Equation
Description
Equations
No. of
Equations
Endogenous
Variables
Exogenous
Variables
Parameters
FACTOR MARKETS
23.
LS = LS 0
Household labor supply
1
LS
24.
TLAB =
Total labor demand
1
TLAB LABi
Labor income
1
Labor migration
1
LMIG PL
Adjusted labor income
1
AYL, PL, LABi
LHHH0
LGOV0
Household adjustment factor
1
adjL LMIG
LS0
Total capital demand
1
TCAP CAPi
å LABi
LS0
i
ö
ø
æ
è
LY = ALY + PLROC0 ⋅ç LMIG2 − LMIG ÷⋅ 0.5
25.
æ
è
ö
ø
ALY PL
− PL⋅ ç LMIG 2 + LMIG ÷⋅ 0.5
(
)
L
PL
⋅η
PLROC 0
26.
LMIG = LS 0 ⋅ log
27.
ALY = PL ⋅ å LAB i + LHHH0 + LGOV0
i
28.
adjL =
29.
(
TCAP =
LS0 + LMIG
)
LMIG
LS0
å CAPi
i
PLROC0
LSO PLROC0
ηL
Table 4.1 (Continued)
Equation
30a.
30b.
Description
Equations
KY = å PK i ⋅ CAPi
i
ö
æ
KY = å CAP PKL + PKROC0 ⋅ ç KMIG 2 -KMIG ÷ ⋅ 0.5−
i
ø
è
i
PKL ⋅ æ
ç KMIG 2 + KMIG ö÷ ⋅ 0.5
No. of
Equations
Capital income short-run
1
Capital income long run
1
Endogenous
Variables
Exogenous
Variables
Parameters
PKi KY CAPi
KY CAPi
PKROC0
PKL KMIG
ø
è
Capital migration
31a.
KMIG = 0
31b.
æ PKL ö K
KMIG = å KSO ⋅logç
÷ ⋅η
i
i
è PKROC 0 ø
32.
TY =
1
KMIG
Capital migration
(long run equilibrium)
1
KMIG PK
Land income
1
TY LANDga PTag
Enterprise income
1
YENT KY
ktax
Retained earnings
1
RETENT KY
retr
(Short run equilibrium)
å LANDag PTag
KS0i PRROC0
ηK
ag
INSTITUTIONAL ACCOUNTS
(
33.
YENT = KY ⋅ 1 − Ktax
34.
RETENT = ret ⋅ KY
)
Table 4.1 (Continued)
Equation
Description
Equations
(
YH = ALY ⋅ 1 − sstax
)
(
No. of
Equations
æ
è
adjL ⋅ TRGOV 0 − ç
(
= YH ⋅ 1 − hhtax
DYH
37.
HSAV = mps ⋅ YH
38.
INV =
39.
Parameters
)
(adjL − 1)2 − (adjL − 1)ö÷ ⋅ 0.5
)
et
YH ALY TY
REMIT 0
Household income
1
YENT RETENT
sstax
TRGOV 0
ø
∗ [TY ⋅ (1−ttax )+(YENT - RETENT − et ⋅ KY ) + REMIT 0]
36.
Exogenous
Variables
+ TY ⋅ 1 − ttax +
(YENT − RETENT-etKY )+ REMIT 0 +
35.
Endogenous
Variables
KY adjL
ttax
Disposable income
1
DYH YH
hhtax
Household saving
1
HSAV YH
mps
Total investment
1
INV QINVi PI
AHEXP = DYH − HSAV- PL ⋅ LHHH 0
Household expenditure
1
AHEXP DYH
HSAV PL
40.
GRP = LY + KY + TY + IBTX
Gross regional product
1
GRP LY KY TY
IBTX
41.
IBTX =
Indirect business tax
1
IBTX XI
åi QINV P
i i
å ibtaxi ⋅ X i
LHHH0
ibtaxi
i
GOVEXP =
42.
å QGOVi ⋅ Pi + adjL ⋅ TRGOV0
i
+ PL ⋅ LGOV 0 + GOVITR0
Government expenditures
1
QGOV , GOVEXP
i
P i PL
LGOV0
TRGOV0
GOVITR0
Table 4.1 (Continued)
Equation
Description
Equations
æ
ö
(
YGOV =ç å ibtax PX X ÷ + sstax ⋅ ALY
i i i
èi
ø
43.
(
No. of
Equations
)
)
+ ktax ⋅ KY + et ⋅ KY + ttax ⋅ TY + hhtax ⋅ YH
Government revenue
1
+ GOVBOR0 + GOVITR 0 + ROWGOV 0
44.
SAV = HSAV + RETENT + ROWSAV 0
Endogenous
Variables
Exogenous
Variables
Parameters
YGOV PX i
GOVBOR0
ibtax i sstax
X i ALY KY
GOVITRO
ktax ttax
TY YH
ROWGOV0
hhtax
SAV HSAV
Total Saving
ROWSAV0
1
RETENT
EQUILIBRIUM OF MARKETS
45.
46.
M i = TVM i + QM i + QGOVM i + QINVM i
X i + M i = TVi + Q i
+ QGOVi + QINVi + EXPi
Total regional imports
n
M i TVM i QM i
QGOVM i QINVM i
Commodity market
equilibrium
n
X M TV Q
i i i i
QGOVi QINVi EXPi
LHHH0
LGOV0
47.
å LAB i + LHHHO + LGOV0 = LS + LMIG
i
Labor market equilibrium
l
LS LMIG LABi
48a.
CAPi = KS 0i
Capital market
equilibrium (short
run equilibrium)
n
CAPi
KS0i
48b.
å CAPi = å KS 0 i + KMIG
i
i
Capital market
equilibrium (long
run equilibrium)
1
CAPi KMIG
KS0i
Table 4.1 (Continued)
Equation
49.
Description
Equations
LANDi = TS 0i
Land market equilibrium
No. of
Equations
1
Endogenous
Variables
Exogenous
Variables
LANDi
Parameters
TS0i
EQUILIBRIUM PRICES
50.
PN i = PX i − å a ji P j − ibtax i PX i
j
51.
Pi =
52.
PX i =
PRi Ri + PM 0i M i
Ri + M i
PR R + PEO EXP
i i
i
i
R + EXP
i
i
Net price
n
PNi , PXi , Pi
aij , ibtaxi
Composite commodity price
n
Pi PRi Ri Mi
PM0i
n
PR PXi Ri EXPi
PEOi
Composite price
faced by producer
________________________________________________________________________________________________________________________________
WELFARE MEASURE
Compensating Variation:
ö
æ 1 ö éæç
÷ êç AHEXPh − adjL å PX jγ jh ÷÷
ç
è 1 − β 0 h ø êëè
j
ø
ö
æ
− ç adjLh HEXP0 h − adjL å P0 j γ jh ÷
ø
è
j
ù
β
æ PX ö β ih æ
PL ö 0 h ú
i÷
÷÷
çç
∏ çç
, ijεM, NR,
÷
PL
P
0
0ø
è
ú
i è iø
û
CVh =
Changes in Compensating
Variation by Household
Income Group
h
Changes in Equivalent
Variation by Household
Income Group
h
Equivalent Variation:
ö
öéæ
÷êçç AHEXPh − adjL å PX jγ jh ÷÷
j
øëè
ø
βih
β
æ P 0i ö æ PL0 ö 0 h
÷
Πç
÷ ç
i è PX i ø è PL ø
ù
æ
ö
−çè adjL HEXP 0 ÷ø − adjL å P 0 γ ú , ijεM, NR,
h
h
j jû
j
æ 1
EVh = ç
è 1 − β0h
A Guide to the GAMS-input-file
This is a user's guide to the GAMS-input-file of the regional CGE
model described throughout section 3. It transforms the mathematical
program specified in section 4.1 into an executable computer program
based in GAMS (the acronym stands for General Algebraic Modeling
System). To make this chapter self-contained we reproduce some
introductory material on the construction of a CGE-model in GAMS,
however we recommend the reading of GAMS tutorial (Brooke et al., Chap.
2).
We provide the complete GAMS-PROGRAM in this link {click here to
download CRS2.GMS}. It’s clearly only a prototype and the numerical
values of the parameters and initial values were explained in section
3.2. For a collection of models with similar specification, but somehow
more sophisticated, we offer the following link: {Oklahoma State University;
Department of Agricultural Economics; RCGE}
In what follows, the GAMS-Program input file is presented and
explained in its major components.
Index sets
The application starts with a definition of the main index sets and
subsets. A set declaration consists of declaring and specifying the
index to be used. Sets should be declared before their subsets. Every
declaration consists of a logical name, a label field, followed by a
list of elements of the index set. As such, it is the same as indexes
used in the equations of the model. They correspond to the subscription
notation of table 4.2{click here to go to table 4.2}.
$TITLE REGIONAL CGE MODEL FOR OKLAHOMA (1993)(CRS.GMS)
$OFFSYMLIST OFFSYMXREF OFFUPPER
SETS
i
Sectors
/Agr
agriculture
Min
mining
Man
manufacture
SER services/
ag(i)
Agricultural sectors
/ AGR/
nag(i)
Nonagricultural market sectors
/ MIN, SER, MAN/
f
Factors
fl(f)
Factors not land / L, K/
/L
land/
ALIAS(i,j);
144
labor, K
capital, T
A $-sign at the beginning of the program, is used for special
commands, i.e., $TITLE, where we introduce the title of the model. All
GAMS-statements end with a semicolon. The ALIAS-statement defines an
alternative name for an index set (subscript).
BASE YEAR DATA
Base year variables are based upon the Social Accounting Matrix
(SAM) and are distinguished
by "0" as a suffix in their names, i.e.,
L0(i) states base year labor. GAMS requires a DECLARATION and
ASSIGNMENT of each variable or parameter. Here, we declare the base
year variables as parameters. GAMS offers flexible arrangements for
introducing the parameters (variables). We recommend first to declare
(initiate) all the parameters, then use tables to enter data and
finally, assign the values.
To provide better readability, parameters are declared by blocks:
prices, production, income and expenditure blocks. In GAMS, commentlines and text in general are introduce by “*” in the first column of a
row.
*#####-- DECLARATION OF BASE YEAR VARIABLES (AS PARAMENTERS)
PARAMETERS
*@Price block
PL0
Wage rate
PLROC0
Wage rate of rest-of-country
PKROC0
Cap rate of rest-of-country
PK0(i)
cap rate
PT0(ag)
Land rent
PE0(i)
Export price
PM0(i)
Import price
PR0(i)
Reg price
P0(i)
Composite price
PN0
Net output price or value-added price of
sector i
PX0(i)
Composite price face for producers
*@Production block
L0(i)
Labor demand
LS0
Labor supply by hh
TLS0
Total labor supply
LHHH0
Labor employed by household group
LGOV0
Labor employed by gov
K0(i)
capital demand
T0(i)
Land demand
KS0
Supply of pri capital
TKS0
Total pri capital supply
TS0
Supply of land
VA0(i)
Value added
V0(j,i)
Composite intermediate good demand
TV0(i)
Composite intermediate good total demand
VR0(j,i)
Reg int good demand
VM0(j,i)
Imported int good demand
TVR0(i)
Reg int good total demand
TVM0(i)
Imported int good total demand
IBT0(I)
Indirect business taxes
X0(i)
Sector output
145
E0(i)
M0(i)
R0(i)
*@Income block
LY0
KY0
TY0
YENT0
YH0
DYH0
HSAV0
SAV0
ROWSAV0
TRGOV0
REMIT0
household
YGOV0
ENTY0
GOVITR0
GOVBOR0
GRP0
Export of reg product
Import
Reg supply of reg product
Labor income
capital income
Land income
Gross Enterprise income
Household income
Disposable hh income
Household saving
Total saving
Saving from rest-of-world
Gov transfer to hh
Remittance from outside the region to
Gov revenue
Enterprise income distrib to hhs
Inter gov transfer
Government Borrowing
Gross regional product
*@Expenditure block
HEXP0
Household expend
QR0(i)
Demand for reg consump good
QM0(i)
Demand for imp consump good
Q0(i)
Demand for comp consump good
GOVEXP0
government expenditure
QGOVR0(i)
government demand for reg good
QGOVM0(i)
government demand for imported good
QGOV0(i)
government demand for comp good
QInvR0(i)
Invest demand for reg good
QInvM0(i)
Invest demand for imported good
QInv0(i)
Invest demand for comp good
INV0
Total invest
The following variables are defined as
"logical variables". A
logical variable takes the value of 1 if the condition stated is true
and "0" if not.
We use these variables when defining an equation or
for assigning value to a particular variable depending on the "true" or
"false" condition of a specific condition, i.e., variable NZV takes the
value of “1” if both regional and imported intermediate input are used,
according to the following graph.
*************************************
*Regional
x
x
0
0
*Import
x
0
x
0
*
*NZV
T
F
F
F
*ZVR
F
F
T
F
*ZVM
F
T
F
T
*************************************
0=zero, x=not zero
T=TRUE,
F=FALSE
ZVM(i,J) non imported intermediate demand with-or-without
regional interm. demand
ZVR(i,J) only imported intermediate demand
NZV(i,J) both imported intermediate demand and regional
demand
ZQM(i)
non imported final demand and either none or
some regional final demand for household
146
ZQR(i)
only imported final demand for household
NZQ(i)
both imported final demand and regional final
demand for households
ZGOVM(i)
ZGOVR(i)
NZGOV(i)
ZInvM(i)
ZInvR(i)
NZInv(i)
DECLARATION OF PARAMETERS TO BE CALIBRATED
These parameters are those specified in Table 4.5. {Click here to see
table 4.5}. They are declared in the following segment of the application
but they will be initialized later.
*#####-- DECLARATION OF PARAMETERS TO BE CALIBRATED.
PARAMETERS
*This parameters are those specified in Table 5.5.
*@Production block
a0(i)
composite value added req per unit of
output i
a(j,i)
req of interm good j per unit of good i
Alpha(i,f)
value added share param
Ava(i)
value added shift param
RHOv(i)
interm input subs param
deltav1(j,i)
deltav(j,i)
interm input share param
Av(j,i)
interm input shift param
RHOx(i)
output transformation param
deltax1(i)
deltax(i)
output share param
Ax(i)
output shift param
*@Income block
ktax
capital tax rate
sstax
factor income tax rate for labor
ttax
factor income tax rate for land
retr
rate of retained earnings fr ent inc
et
enterprise tax rate
hhtax
income tax rate for hh
ltr
Household Income Transfer Coefficient
mps
saving rate
ibtax(i)
indirect business tax
beta(i)
param calc fr elast of comm demand wrt inc
*@Expenditure block
RHOq
consumer demand subs param
deltaq1(i)
deltaq(i)
consumer demand share param
Aq(i)
consumer demand constant eff param
RHOgov
gov demand subs param
deltagov1
deltagov
gov demand share param
Agov
gov demand constant eff param
RHOinv
inv gov demand subs param
147
deltainv1
deltainv
Ainv
;
inv gov demand share param
inv gov demand constant eff param
DATA
Data comes from our SAM (Table 2.1). {Click here to see table 2.1} You
should note that values from our SAM are scaled to millions of dollars
instead of thousands. Though the scaling of our data is not a “must”
for solving the model, we strongly recommend scaling. Scaling problems
have been found to create more serious problems in more disaggregated
models.
Table
AGR
AGR
MIN
MAN
SER
;
Table
AGR
MIN
MAN
SER
IOR(i,j) Input-output regional matrix
MIN
675.798
123.47
159.671
381.542
MAN
8.115
2180.942
1390.701
1317.332
IOM(i,j)
AGR
MIN
579.870
11.850
446.830
155.160
SER
863.991
1258.117
3594.97
5272.186
34.800
881.343
3953.2
9752.027
Input-output import matrix
MAN
SER
5.160 378.422
41.300
1274.869
311.094
385.272
450.977
8835.472
2750.345
458.802
1886.710
4188.764
;
Table VAD(i,f) Value
L
AGR
433.242
MIN
1622.806
MAN
7577.427
SER
20767.388
;
Table HHCONR(i,*)
added matrix
K
571.360
2713.109
4025.159
12042.708
T
709.066
Household consumption demand for regional
goods
AGR
MIN
MAN
SER
;
HOUSE
147.210
1587.998
2656.085
30727.366
Table HHCONM(i,*)
Household consumption demand for imported
goods
AGR
MIN
MAN
SER
;
HOUSE
181.550
141.662
5713.705
9510.103
Table GOVCONR(i,*)
regional goods
Government
148
consumption
demand
for
AGR
MIN
MAN
SER
;
GOV
12.863
231.250
1854.066
1477.995
Table
GOVCONM(i,*)
imported goods
GOV
AGR
20.097
MIN
29.912
MAN
823.846
SER
542.893
;
Government
consumption
demand
for
Table FYDIST(*,f) Factor income distribution to households
L
K
T
HH
31363.057
0.00
683.300
;
TABLE ParamA(*,i)
BASE YEAR VALUES FOR INDUSTRY
AGR
MIN
MAN
SER
PT0
1.00
1.00
1.00
PK0
1.00
1.00
1.00
PR0
1.00
1.00
1.00
P0
1.00
1.00
1.00
PM0
1.00
1.00
1.00
PE0
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
1.00
X0
59115.190
R0
49486.101
E0
9629.089
M0
16920.731
IBT0
4318.043
QINVR0
557.653
QINVM0
178.299
SIGMAp
1.00001
SIGMAv
4
SIGMAx
0.70
SIGMAq
2.00
SIGMAgov
2.00
4344.160
12089.784
34190.427
1752.557
6282.217
18360.150
2591.603
5807.567
15830.277
1216.846
96.301
2170.418
666.971
21475.978
186.879
9.780
19.097
4751.457
10.447
15.759
2454.803
1.00001
1.42
1.00001
0.5
1.00001
3.55
3.90
2.90
2.90
1.42
0.50
3.55
1.42
0.50
3.55
149
SIGMAinv
1.42
0.50
3.55
2.00
;
TABLE ParamB(f,*)
BASE YEAR VALUES FOR FACTORS
WAGE0
WAGEROC0
FTAX0
RETENT0
CAPROC0
L
1.0
1.0
6126.715
0
K
-1006.686
9077.096
1
T
25.766
0
;
TABLE ParamC (*,*)
HOUSE
+
HOUSE
;
CAP0
1
BASE YEAR VALUES FOR HOUSEHOLD GROUPS
HTAX0
6976.571
HSAV0
-3869.320
REMIT0
760.824
TRGOV0
11490.516
ENTYDIS0
9582.303
TABLE ParamD(g,*)
BASE YEAR VALUES FOR GOVTS
BOR0
GOVDR0
GOVDM0
GOV
0.0
3576.174
1416.748
;
SCALAR LHHH0
Labor used by household / 107.070/;
SCALAR LGOV0
Labor used by government
/6981.839/;
SCALAR GOVITR0
Inter-government transfers
/8477.813/;
SCALAR YENT0
Enterprise income
/20359.022/;
SCALAR ENTTAX0
Enterprise taxes
/1699.623/;
SCALAR ROWGOV0
Rest of world transfers to government
/4375.094/;
SCALAR ROWSAV0
Saving from ROW
/2789.519/;
SCALAR QINVMSUM0 Investment demand for imported goods /
2659.308/;
SCALAR etaL
Labor migration elasticity
/
.92
/;
SCALAR etaK
Capital migration elasticity
/
.92
/;
Scalar KMobil
Capital Mobility
/
1.0
/;
ASSIGNING VALUES: Initialization of Parameters
Here, we assign a value to each of the base year variables
declared previously. This assigning of values should correspond to our
SAM.
*@Production block
L0(i)
=VAD(i,"L");
K0(i)
=VAD(i,"K");
T0(i)
=VAD(i,"T");
VA0(i)
=sum(f,VAD(i,f));
V0(j,i)
=IOR(j,i)+IOM(j,i);
TV0(i)
=sum(j,V0(i,j));
VM0(j,i)
=IOM(j,i);
VR0(j,i)
=IOR(j,i);
TVM0(i)
=sum(j,VM0(i,j));
TVR0(i)
=sum(j,VR0(i,j));
LHHH0
=LHHH0;
150
LGOV0
LS0
X0(i)
E0(i)
R0(i)
KS0(i)
TKS0
TS0(i)
IBT0(I)
=LGOV0;
=sum(i,VAD(i,"L"))+LHHH0+LGOV0;
=ParamA("X0",i);
=ParamA("E0",i);
=ParamA("R0",i);
=VAD(i,"K");
=sum(i,KS0(i));
=VAD(i,"T");
=PARAMA("IBT0",I);
*@Income block
TRGOV0
=ParamC ("HOUSE","TRGOV0");
LY0
=sum(i,VAD(i,"L"))+LHHH0+LGOV0;
KY0
=sum(i,VAD(i,"K"));
TY0
=sum(i,VAD(i,"T"));
YENT0
=YENT0;
REMIT0
=ParamC ("HOUSE","REMIT0");
YH0
=sum(f,FYDIST("HH",f))+ParamC("HOUSE","ENTYDis0")+TRGOV0
+REMIT0;
DYH0
=YH0 -ParamC ("HOUSE","HTAX0");
HSAV0
=ParamC ("HOUSE","HSAV0");
HEXP0
=DYH0-HSAV0-LHHH0;
SAV0
=ParamB("K","RETENT0")+
("HOUSE","HSAV0")+ROWSAV0;
ROWSAV0
=ROWSAV0;
YGOV0
=sum(i,ParamA("IBT0",i))+sum(f,ParamB(f,"FTAX0"))
ParamC
+ParamC("HOUSE","HTAX0")+ENTTAX0+ROWGOV0+GOVITR0;
ENTY0
=ParamC("HOUSE","ENTYDis0");
GOVBOR0
=ParamD("GOV","BOR0");
GRP0
=LY0+KY0+TY0+sum(i,ParamA("IBT0",i));
*@Expenditure block
QR0(i)
=HHCONR(i,"HOUSE");
QM0(i)
=HHCONM(i,"HOUSE");
Q0(i)
=QM0(i)+QR0(i);
GOVEXP0
=ParamD("GOV","GOVDR0")+ParamD("GOV","GOVDM0")
+ParamC("HOUSE","TRGOV0")+LGOV0+GOVITR0;
QGOVR0(i)
=GOVCONR(i,"GOV");
QGOVM0(i)
=GOVCONM(i,"GOV");
QGOV0(i)
=QGOVM0(i)+QGOVR0(i);
QINVR0(i)
=ParamA("QINVR0",i);
QINVM0(i)
=ParamA("QINVM0",i);
QINV0(i)
=QINVM0(i)+QINVR0(i);
INV0
=sum(i,QINV0(i));
M0(i)
=ParamA("M0",i);
*@Price block
PL0
=ParamB("L","WAGE0");
PK0(i)
=ParamA("PK0",i);
PLROC0
=ParamB("L","WAGEROC0");
PKROC0
=ParamB("K","CAPROC0");
PT0(ag)
=ParamA("PT0",ag);
PE0(i)
=ParamA("PE0",i);
PM0(i)
=ParamA("PM0",i);
PR0(i)
=ParamA("PR0",i);
P0(i)
=ParamA("P0",i);
PX0(i)
=(PR0(i)*R0(i)+PM0(i)*M0(i))/(R0(i)+M0(i));
*---------------------------------------------------* Regional
x x 0 0
0=zero, x=not zero
151
* Import
x 0 x 0
*
* NZV
T F F F
T=True, F=False
* ZVR
F F T F
* ZVM
F T F T
*---------------------------------------------------ZVM(i,j)
ZVR(i,j)
NZV(i,j)
ZQM(i)
ZQR(i)
NZQ(i)
ZGOVM(i)
ZGOVR(i)
NZGOV(i)
ZInvM(i)
ZInvR(i)
NZInv(i)
=(VM0(i,j) eq 0);
=(VR0(i,j) eq 0) and (VM0(i,j) ne 0);
=(VR0(i,j) ne 0) and (VM0(i,j) ne 0);
=(QM0(i) eq 0);
=(QR0(i) eq 0) and (QM0(i) ne 0);
=(QR0(i) ne 0) and (QM0(i) ne 0);
=(QGOVM0(i) eq 0);
=(QGOVR0(i) eq 0) and (QGOVM0(i) ne 0);
=(QGOVR0(i) ne 0) and (QGOVM0(i) ne 0);
=(QInvM0(i) eq 0);
=(QInvR0(i) eq 0) and (QInvM0(i) ne 0);
=(QInvR0(i) ne 0) and (QInvM0(i) ne 0);
So far, we have assigned values to our base year variables
(parameters). Has GAMS read the assignments correctly? Next, we define
new parameter to check for accuracy of our assignment statements. If
correct, we should get our SAM and a block of unity prices. Though, the
DISPLAY statement of GAMS allows the modeler to easily see the
assignment results with statements like
DISPLAY PK0, PT0, L0, K0,TSO;
we prefer to define new parameters, so the output will be easier
to read and presented in table format. The advantage of this procedure
may not be appreciated in small CGE models, but definitely are greatly
appreciated in much bigger models.
PARAMETER SAM1 SOCIAL ACOUNTING MATRIX -BASE YEAR PRICES-;
SAM1(I,"PK")=PK0(I);
SAM1(ag,"PT")=PT0(ag);
SAM1(I,"PE0")=PE0(I);
SAM1(I,"PM0")=PM0(I);
SAM1(I,"PR0")=PR0(I);
SAM1(I,"P0")=P0(I);
SAM1(I,"PR0")=PR0(I);
PARAMETER SAM2 SOCIAL ACCOUNTING MATRIX -BASE YEAR DATA-;
SAM2(I,"L0")=L0(I);
SAM2(I,"K0")=K0(I);
SAM2(I,"KS0")=KS0(I);
SAM2(I,"T0")=T0(I);
SAM2(I,"TS0")=TS0(I);
SAM2(I,"VA0")=VA0(I);
SAM2(I,"TVR0")=TVR0(I);
SAM2(I,"TVM0")=TVM0(I);
SAM2(I,"TV0")=TV0(I);
SAM2(I,"IBT0")=IBT0(I);
SAM2(I,"X0")=X0(I);
SAM2(I,"M0")=M0(I);
SAM2(I,"R0")=R0(I);
SAM2(I,"E0")=E0(I);
SAM2(I,"Q0")=Q0(I);
SAM2(I,"QR0")=QR0(I);
SAM2(I,"QM0")=QM0(I);
SAM2(I,"QGOV0")=QGOV0(I);
152
SAM2(I,"QGOVR0")=QGOVR0(I);
SAM2(I,"QGOVM0")=QGOVM0(I);
SAM2(I,"QINV0")=QINV0(I);
SAM2(I,"QINVR0")=QINVR0(I);
SAM2(I,"QINVM0")=QINVM0(I);
OPTION DECIMALS=0;
DISPLAY SAM1;
OPTION DECIMALS=3;
DISPLAY SAM2;
DISPLAY V0,VM0,VR0,LS0,PL0, PLROC0,LHHH0,LGOV0,LY0,KY0,TY0,
YENT0,REMIT0,YH0,DYH0,YGOV0,GRP0,HSAV0,HEXP0,GOVEXP0,SAV0,RO
WSAV0,
TRGOV0,ENTY0,ENTTAX0,GOVBOR0;
PARAMETER CALIBRATION
Calibration is the setting of model parameters in order to make
the equilibrium solution fit the data of a given base year (our SAM).
The way to perform this adjustment in GAMS is to solve at fixed
(consistent) values of observed variables, treating some of the
parameters as variables. The solution will then fit the model to the
data.
The calibration procedure was introduced in section 2.3. We have
linked the text equation that is used in the calibration with each of
our definitions; i.e., clicking over the definition
a0(i)
= VA0(i)/X0(i);
takes you to equation 3.1.2 in our text. Once again, remember that our
base year variables are identified by a “0” suffix in the name.
*##########################################################*
*
*
*
PARAMETER CALIBRATION
*
*
*
*##########################################################*
*#####-- CALIBRATION
*@Production block
a0(i)
=VA0(i)/X0(i);
a(j,i)
=V0(j,i)/X0(i);
alpha(ag,"K")
=VAD(ag,"K")/VA0(ag);
alpha(ag,"T")
=VAD(ag,"T")/VA0(ag);
alpha(ag,"L")
=1-alpha(ag,"K")-alpha(ag,"T");
alpha(nag,"K") =VAD(nag,"K")/VA0(nag);
alpha(nag,"L") =1-alpha(nag,"K");
Ava(ag)
=VA0(ag)/Prod(f,VAD(ag,f)**alpha(ag,f));
Ava(nag)
=VA0(nag)/PROD(fl,VAD(nag,fl)**alpha(nag,fl));
RHOv(i)
=1-1/ParamA("SIGMAv",i);
deltav1(j,i)
$(NZV(j,i))
=(VR0(j,i)/VM0(j,i))**(1RHOv(j))*(PR0(j)/PM0(j));
deltav(j,i)
$(NZV(j,i))
=1/(1+deltav1(j,i));
153
Av(j,i)
$(NZV(j,i))
=V0(j,i)/(deltav(j,i)*VM0(j,i)**RHOv(j)
+(1-deltav(j,i))
*VR0(j,i)**RHOv(j))**(1/RHOv(j));
RHOx(i)
=1+1/ParamA("SIGMAx",i);
deltax1(i)
=(R0(i)/E0(i))**(1RHOx(i))*(PR0(i)/PE0(i));
deltax(i)
=1/(1+deltax1(i));
Ax(i)
=X0(i)/(deltax(i)*E0(i)**RHOx(i)+(1deltax(i))
*R0(i)**RHOx(i))**(1/RHOx(i));
*@Income block
sstax
=ParamB("L","FTAX0")/LY0;
ktax
=ParamB("K","FTAX0")/KY0;
ttax
=ParamB("T","FTAX0")/TY0;
retr
=ParamB("K","RETENT0")/sum(i,VAD(i,"K"));
ibtax(i)
=ParamA("IBT0",i)/(PR0(i)*X0(i));
et
=ENTTAX0/KY0;
hhtax
=ParamC("HOUSE","HTAX0")/YH0 ;
ltr
=1;
mps
=ParamC("HOUSE","HSAV0")/YH0 ;
*@Expenditure block
RHOq(i) = 1-1/ParamA("SIGMAq",i);
deltaq1(i)$NZQ(i)
=
(QR0(i)/QM0(i))**(1RHOq(i))*(PR0(i)/PM0(i));
deltaq(i)$NZQ(i) =1/(1+deltaq1(i));
Aq(i)$NzQ(i)
=
Q0(i)/(deltaq(i)*QM0(i)**RHOq(i)+(1deltaq(i))*QR0(i)**RHOq(i))**(1/RHOq(i));
RHOgov(i) = 1-1/ParamA("SIGMAgov",i);
deltagov1(i)$NZGOV(i)
=(QGOVR0(i)/QGOVM0(i))**(1RHOgov(i))*(PR0(i)/PM0(i));
deltagov(i)$NZGOV(i) = 1/(1+deltagov1(i));
Agov(i)$NZGOV(i)
=
QGOV0(i)/(deltagov(i)*QGOVM0(i)**RHOgov(i)+(1deltagov(i))*QGOVR0(i)**RHOgov(i))**(1/RHOgov(i));
RHOinv(i)= 1-1/ParamA("SIGMAinv",i);
deltainv1(i)$NZInv(i)
=
(QINVR0(i)/QINVM0(i))**(1RHOinv(i))*(PR0(i)/PM0(i));
deltainv(i)$NZInv(i) = 1/(1+deltainv1(i));
Ainv(i)$NZInv(i)
=
QINV0(i)/(deltainv(i)*QINVM0(i)**RHOinv(i)+(1deltainv(i))*QINVR0(i)**RHOinv(i))**(1/RHOinv(i));
beta(i) = Q0(i)*P0(i)/HEXP0;
To check values for the calibration we use the following
parameters which allow us to display the results of calibration in a
table-like display.
PARAMETER CALIBR PARAMETER CALIBRATED;
CALIBR(I,"A0")=A0(I);
CALIBR(I,"AVA")=AVA(I);
CALIBR(I,"RHOV")=RHOv(I);
CALIBR(I,"RHOQ")=RHOQ(I);
CALIBR(I,"DELTAQ")=DELTAQ(I);
CALIBR(I,"AQ")=AQ(I);
CALIBR(I,"IBTAX")=IBTAX(I);
CALIBR(I,"RHOGOV")=RHOGOV(I);
CALIBR(I,"DELTAGOV")=DELTAGOV(I);
CALIBR(I,"AGOV")=AGOV(I);
CALIBR(I,"RHOINV")=RHOINV(I);
154
CALIBR(I,"AINV")=AINV(i);
CALIBR(I,"RHOX")=RHOX(i);
CALIBR(I,"DELTAX")=DELTAX(i);
CALIBR(I,"AX")=AX(i);
CALIBR(I,"BETA")=BETA(i);
DISPLAY CALIBR;
DISPLAY a,Av,deltav,alpha,
ktax,sstax,ttax,retr,et,mps,hhtax;
VARIABLE DECLARATION
All symbols belonging to the list of choice variables in the
mathematical
program
should
be
declared
as
VARIABLES,
not
as
PARAMETERS. Endogenous variables are given in table 4.3. {Click here to see
table 4.3} Every endogenous variable declaration has a logical name
followed by a label field (optional).
*##########################################################*
*
*
*
VARIABLE DECLARATION
*
*
*
*##########################################################*
* ENDOGENOUS VARIABLES
VARIABLES
Z
Objective Function Value
*@Price block
PL
PK(i)
PKL
PT(ag)
PN(i)
PR(i)
P(i)
PX(i)
Wage rate
Capital rate
Capital rate in the long run
Land rent
Net price
Regional price
Composite price
Composite price faced by consumers
*@Production block
LAB(i)
CAP(i)
LAND(ag)
TCAP
TLAB
LS
LMIG
KMIG
VA(i)
V(j,i)
VM(j,i)
VR(j,i)
R(i)
X(i)
EXP(i)
M(i)
TVM(i)
TVR(i)
TV(i)
adjL
Labor demand
Capital demand
Land demand
Total Capital Demand
Total Labor Demand
Labor supply
Labor migration
Capital migration
Value added
Composite intermediate good demand
Imported int good demand
Reg int good demand
Regional supply
Output
Export
Import
Imported int good total demand
Reg int good total demand
Composite intermediate good total demand
Labor adjustment
*@Income block
155
LY
ALY
migrating)
KY
TY
YENT
RETENT
YH
(including in-migrants)
DYH
region + inmigra)
HSAV
SAV
INV
YGOV
IBTX
GRP
Labor income (original hhs)
Adjusted labor income (staying + incapital income (original capital stock)
Land income
Enterprise income
Retained Earnings by enterprises
Income of hh staying in the region
Disposable hh income (staying in the
Household saving (staying +inmigrat)
Total saving
Investment
gov revenue
Indirect business tax
Gross region product
*### Expenditure block
AHEXP
Adjusted household expenditure (spent
within the region)
Q(i)
Demand for comp consump good
QM(i)
Demand for imp consump good
QR(i)
Demand for reg consump good
GOVEXP
gov expend
QGOV(i)
gov demand for comp good
QGOVM(i)
gov demand for imported good
QGOVR(i)
gov demand for reg good
QINV(i)
Invest gov demand for comp good
QINVM(i)
Invest gov demand for imported good
QINVR(i)
Invest gov demand for reg good
SLACK(i)
SLACK2(i)
The following statement ensures that we are working with positive
variables. All variables may be assigned as positive variables except
the “Z” variable which we use in the optimization statement.
POSITIVE VARIABLE
SLACK, SLACK2;
Equation Declaration
This section declares the equations of the model which are those
presented in Table 4.1. {Click here for table 4.1} Equations are also
denoted by symbols. Hence, every equation can be referred to by its
logical name.
*##########################################################*
*
*
*
EQUATION DECLARATION
*
*
*
*##########################################################*
*This section declares the equations of the model
*which are those presented in table 5.1
EQUATIONS
EQZ
*@Price block
NETprice(i)
Price(i)
Price1(i)
objective function
net price
composite price
156
*@Production block
Ldemand(i)
labor demand
KdemandSR(i)
capital demand
KdemandLR(i)
Tdemand(ag)
land demand
TLdem
total labor demand
TKdem
total capital demand
VAdemand(i)
value added demand
Vdemand(j,i)
intermediate demand
VAprod1(nag)
value added prod fc
VAprod2(ag)
value added prod fc
Vces(j,i)
ces fc for int demand
TVdemand(i)
intermediate total demand
TVRdemand(i)
int reg total demand
TVMdemand(i)
int imp total demand
VRdem(j,i)
demand for reg int good
VRdem0(j,i)
demand for reg int good for goods with
zero import
VMDem0(j,i)
demand for imp int good for goods with
zero import
Xcet(i)
cet fc for reg product
Rsupply(i)
reg supply of reg product
LSupply
labor supply
LMIGrat
labor migration
adjustL
labor migration adjustment
KMIGrat
capital migration
KMIGrat1
*@Income block
LYincome
ALYincome
KYincomeSR
KYincomeLR
TYincome
YENTincome
RETearn
YHincome
DHYincome
HSAVings
SAVings
INVest
YGOVincome
INDtax
GRProduct
labor income
adjusted labor income
capital income
land income
enterprise income
Retained earning by enterprises
household income
disposable income
household savings
total savings
total investment
Government income
Indirect business tax
gross region product
*@Expenditure block
AHEXPLow
adj. household expenditure
Qces
ces fc for consumption
Qdemand
cons demand for composite good
QRdem0
cons demand for reg goods
QRdem1
QRdem2
QMdem1
QMdem2
GOVEXPend
Gov expenditure
QGOVces
ces for st and loc gov demand
QGOVdemand
st and loc gov cons
QGOVRdem0
st and loc gov reg cons
QGOVRDem1
QGOVRDem2
QGOVMDem1
QGOVMDem2
157
QINVces
QINVemand
QINVRdem0
QInvRdem1
QInvRdem2
QInvMdem1
QInvMdem2
Mimports(i)
ces for invest gov demand
invest gov cons
invest gov reg cons
import
*@Equilibrium
COMMequil(i)
Lequil
Kequil(i)
Kequil1
Tequil(ag)
comm market equilibrium
labor market equilibrium
cap market equilibrium
land market equilibrium;
EQUATION DEFINITION
All equations are defined following the algebraic specification
given in Table 4.1. {Click here to see table 4.1.} This section requires
special attention and intense scrutiny. To help the reader, we have
linked each equation definition. Thus, it is possible to move from
GAMS-specification format to its algebraic specification. Furthermore,
each algebraic equation in Table 4.1 is itself linked to the part of
the text where derivation takes place.
In the equation definition, the “=E=” represents an equalitysign; the greater-or-equal sign is written as =G=, and smaller-or-equal
as =L=. Thus, by comparing with Table 5.1 algebraic specification, the
meaning of each equation is straightforward. Exceptions are equations
involving a dollar expression; i.e., QCES(CI)$NZQ(CI). A dollar
expression indicates that the value of the variable (i.e., the equation
QCES) should be considered only if the expression that follows is true.
*##########################################################*
*
*
*
EQUATION DEFINITION
*
*
*
*##########################################################*
*All equations are defined following the algebraic structure
*on table 5.1.
EQZ..
Z
=e= sum(i,SLACK(i)+SLACK2(i));
*@Price block
NETprice(i)..
PN(i)
=e= PX(i)-sum(j,A(j,i)*P(j))ibtax(i)*PX(i);
Price(i)..
P(i)
=e=
(PR(i)*R(i)+PM0(i)*M(i))/(R(i)+M(i));
Price1(i)..
PX(i)
=e=
(PR(i)*R(i)+PE0(i)*Exp(i))/(R(i)+Exp(i));
*@Production block
Ldemand(i)..
LAB(i) =e= alpha(i,"L") *PN(i)*X(i)/PL;
KdemandSR(i)$(Not
Kmobil)..
CAP(i)
=e=
alpha(i,"K")*PN(i)*X(i)/PK(i);
KdemandLR(i)$(Kmobil)..
CAP(i)
=e=
alpha(i,"K")*PN(i)*X(i)/PKL;
Tdemand(ag)..
LAND(ag)=e=
alpha(ag,"T")
*PN(ag)*X(ag)/PT(ag);
158
TLdem..
TLAB =e= Sum(i,LAB(i));
TKdem..
TCAP =e= Sum(i,CAP(i));
LSupply ..
LS
=e= LS0;
LMIGrat ..
LMIG =e= etaL*LS0*LOG(PL/PLROC0);
adjustL..
adjL =e= (LS0+LMIg)/LS0;
KMIGrat$(KMobil)..
KMIG
=e=etaK*(SUM(i,K0(i))*LOG(PKL/PKROC0));
KMIGrat1$(not KMobil).. KMIG
=e= 0;
VAdemand(i)..
VA(i)+SLACK(i)+SLACK2(i)=e= a0(i)*X(i);
VAprod1(nag)..
VA(nag)
=e=
Ava(nag)*LAB(nag)**alpha(nag,"L")*CAP(nag)**
alpha(nag,"K");
VAprod2(ag)..
VA(ag)
=e=
Ava(ag)*LAB(ag)**alpha(ag,"L")*CAP(ag)**
alpha(ag,"K")*LAND(ag)**alpha(ag,"T");
Vdemand(j,i)..
V(j,i) =e= a(j,i)*X(i);
Vces(j,i)..
V(j,i) =e= Av(j,i)*(deltav(j,i)*VM(j,i)
**RHOv(j)+(1-deltav(j,i))
*VR(j,i)**RHOv(j))**(1/RHOv(j));
TVdemand(i)..
TV(i)
=e= sum(j,V(i,j));
VRdem(j,i)$NZV(j,i)..
VR(j,i) =e= VM(j,i)*((1-deltav(j,i))/
deltav(j,i)*
PM0(j)/PR(j))**(1/(1RHOv(j)));
VRdem0(j,i)$ZVM(j,i)..
VR(j,i) =e= V(j,i);
VMdem0(j,i)$ZVM(j,i)..
VM(j,i) =e= 0;
TVRdemand(i)..
TVR(i) =e= sum(j,VR(i,j));
TVMdemand(i)..
TVM(i) =e= sum(j,VM(i,j));
Xcet(i)..
X(i)
=e=
Ax(i)*(deltax(i)*EXP(i)**RHOx(i)+(1deltax(i))*R(i)**RHOx(i))
**(1/RHOx(i));
Rsupply(i)..
R(i)
=e=
EXP(i)*((1DELTAx(i))/DELTAx(i)
*PE0(i)/PR(i))**(1/(1RHOx(i)));
INDtax..
IBTX
=E= Sum(i,ibtax(i)*X(i));
GRProduct..
GRP
=e= ALY + KY + TY + IBTX;
*@Income block
*ALY is defined for all labor; LY is defined for original
household
ALYincome..
ALY
=e= PL*(TLAB+LHHH0+LGOV0);
LYincome..
LY
=e= ALY+PLROC0*(SQRT(LMig**2)LMig)*0.5
PL*(SQRT(LMig**2)+LMig)*0.5;
KYincomeSR$(not kmobil)..
KY
=e= sum(i,PK(i)*CAP(i));
KYincomeLR$(kmobil)..
KY
=e=
sum(i,PKL*CAP(i))+PKROC0*(SQRT(KMIG**2)-KMIG)
*0.5PKL*(SQRT(KMIG**2)+KMIG)*0.5;
RETearn..
RETENT =e= retr*KY;
TYincome..
TY
=e= sum(ag,PT(ag)*LAND(ag));
YENTincome..
YENT
=e= KY*(1-ktax);
YHincome ..
YH
=e= ALY*(1-sstax)
+TY*(1-ttax)+(YENT-RETENTet*KY)
+REMIT0+adjL*TRGOV0
159
-((SQRT((adjL-1)**2)-(adjL1))*0.5)
*(TY*(1-ttax)+(YENT-RETENTet*KY)
DHYincome ..
HSAVings ..
SAVings..
INVest..
YGOVincome..
DYH
=e=
HSAV =e=
SAV
INV
YGOV
+REMIT0);
YH *(1-hhtax );
mps *YH ;
=e= HSAV+RETENT+ROWSAV0;
=e= sum(i,P(i)*QINV(i));
=e= Sum(i,ibtax(i)*PX(i)*X(i))
+sstax*ALY
+ktax*KY+et*KY
+ttax*TY
+hhtax *YH+GOVBOR0+GOVITR0;
*@Expenditure block
AHEXPLow..
AHEXP =e= DYH-HSAV-PL*LHHH0;
Qdemand(i).. Q(i)
=e= beta(i)*AHEXP/P(i);
Qces(i)$NZQ(i).. Q(i) =e= Aq(i)*(deltaq(i)*QM(i)
**RHOq(i)+(1-deltaq(i))*QR(i)**RHOq(i))
**(1/RHOq(i));
QRdem0(i)$NZQ(i)..
QR(i)
=e=
QM(i)*((1deltaq(i))/deltaq(i)
*PM0(i)/PR(i))**(1/(1-RHOq(i)));
QRdem1(i)$ZQM(i).. QM(i) =e= 0;
QMdem1(i)$ZQM(i).. QR(i) =e= Q(i);
QRdem2(i)$ZQR(i).. QR(i) =e= 0;
QMdem2(i)$ZQR(i).. QM(i) =e= Q(i);
GOVEXPend..
GOVEXP
=e=
sum(i,P(i)*QGOV(i))+adjL*
TRGOV0+PL*LGOV0+GOVITR0;
QGOVdemand(i)..
QGOV(i)
=e= QGOV0(i);
QGOVces(i)$NZGOV(i)..
QGOV(i)
=e=
Agov(i)*(deltagov(i)
*QGOVM(i)**RHOgov(i)+(1deltagov(i))
*QGOVR(i)**RHOgov(i))**(1/RHOgov(i));
QGOVRdem0(i)$NZGOV(i)..
QGOVR(i)
=e=QGOVM(i)*((1deltagov(i))
/deltagov(i)*PM0(i)/PR(i))**(1/(1RHOgov(i)));
QGOVRdem1(i)$ZGOVM(i)..
QGOVM(i) =e= 0;
QGOVMdem1(i)$ZGOVM(i)..
QGOVR(i) =e= QGOV(i);
QGOVRdem2(i)$ZGOVR(i)..
QGOVR(i) =e= 0;
QGOVMdem2(i)$ZGOVR(i)..
QGOVM(i) =e= QGOV(i);
QINVemand(i)..
QINV(i) =e= QINV0(i);
QINVces(i)$NZInv(i)..
QINV(i)
=e=Ainv(i)*(deltainv(i)*QINVM(i)
**RHOinv(i)+(1deltainv(i))*QINVR(i)**RHOinv(i))
**(1/RHOinv(i));
QINVRdem0(i)$NZInv(i)..
QINVR(i)=e=
QINVM(i)*((1deltainv(i))
/deltainv(i)*PM0(i)/PR(i))**(1/(1RHOinv(i)));
QInvRDem1(i)$ZInvM(i).. QInvM(i)=e= 0;
QInvMDem1(i)$ZInvM(i).. QInvR(i)=e= QInv(i);
QInvRDem2(i)$ZInvR(i).. QInvR(i)=e= 0;
QInvMDem2(i)$ZInvR(i).. QInvM(i)=e= QInv(i);
Mimports(i)..
M(i)
=e=
TVM(i)+QM(i)+QGOVM(i)+QINVM(i);
*@Equilibrium
160
COMMequil(i)..
X(i)+M(i)=e=TV(i)+Q(i)+QGOV(i)+QINV(i)+EXP(i);
Lequil..
sum(i,LAB(i))+LHHH0+LGOV0 =e= LS0+LMIG;
Kequil1$(KMobil)..
KMig =e= Sum(i,CAP(i)-KS0(i));
Kequil(i)$(not KMobil).. CAP(i)
=e= KS0(i);
Tequil(ag)..
LAND(ag) =e= T0(ag);
STARTING VALUES and BOUNDS
Before a model is solved, it is necessary to initialize all
relevant bounds. Bounds are treated in the same way as parameters.
Here, we introduce GAMS language to characterize a variable. A GAMSvariable is characterized by a suffix:
.L
current level of the variable
.M
shadow price on the bound
.LO
lower bound
.UP
upper bound
.FX
fixed (lower bound=upper bound).
The variables (.L-values) keep their level value from one
solution to the next assignment. Unassigned upper bounds are set at
plus infinity, non-initialized lower bounds at minus infinity. In
direct assignments, variables should be referenced with their suffices.
The initialization is at arbitrary values, in order to test the
computational procedure. However, in empirical applications it is
recommended to initialize the variables at their SAM-values.
*##########################################################*
*
*
*
INITIALIZATION OR STARTING VALUES
*
*
*
*##########################################################*
*@Price block
*@Income block
PL.L
=PL0
;
PKL.L
=1;
PK.L(i)
=PK0(i)
;
PT.L(ag)
=PT0(ag)
;
HSAV.L
=HSAV0
;
PR.L(i)
=PR0(i)
;
YGOV.L
=YGOV0
;
P.L(i)
PX.L(i)
PN.L(i)
=P0(i)
;
= PX0(i)
;
= PX0(i)-sum(j,A(j,i)*P0(j))-ibtax(i)*PX0(i);
*@Production block
SLACK.L(i) =0;
LAB.L(i) =L0(i)
;
CAP.L(i) =K0(i)
;
*
LAND.L(ag) =T0(ag)
;
LS.L
= LS0;
LMIG.L
=0;
KMIG.L
=0;
VA.L(i)
=VA0(i)
;
VM.L(j,i) =VM0(j,i)
VR.L(j,i) =VR0(j,i)
V.L(j,i)
=V0(j,i)
TVM.L(i)
=TVM0(i)
TVR.L(i)
=TVR0(i)
SLACK2.L(i)
=0;
INV.L
=INV0;
GRP.L
=GRP0;
*@Expenditure block
;
;
;
;
QM.L(i) =QM0(i)
;
GOVEXP.L
;
=GOVEXP0
;
TV.L(i)
R.L(i)
=TV0(i)
=R0(i)
;
;
161
QGOV.L(i) =QGOV0(i)
QGOVM.L(i) =QGOVM0(i)
;
;
X.L(i)
=X0(i)
;
QGOVR.L(i) =QGOVR0(i)
EXP.L(i) =E0(i)
;
M.L(i)
=M0(i)
;
Q.L(i)
=beta(i)*HEXP0/PX0(i);
QR.L(i) =QR0(i)
;
*@Income block
LY.L
=LY0
KY.L
=KY0
TY.L
=TY0
adjL.L
=1
;
YENT.L
=YENT0
YH.L
=YH0
;
SAV.L
=SAV0
DYH.L
=DYH0
;
QINVM.L(i) =QINVM0(i)
QINVR.L(i) =QINVR0(i)
QINV.L(i) =QINV0(i)
;
;
;
;
;
;
;
;
;
*##########################################################*
*
*
*
VARIABLE BOUNDS
*
*
*
*##########################################################*
PL.LO
= 0.000001;
PT.LO(ag)
= 0.000001;
PK.LO(i)
= 0.000001;
PR.LO(i)
= 0.000001;
PN.LO(i)
= 0.000001;
P.LO(i)
= 0.000001;
R.LO(i)
= 0.000001;
PX.LO(i)
= 0.000001;
QM.LO(i)$(QM0(i) ne 0) = 0.000001;
QR.LO(i)$(QR0(i) ne 0) = 0.000001;
Q.LO(i)$(Q0(i) ne 0)
= 0.000001;
QM.LO(i)$(QM0(i) eq 0) = 0;
QR.LO(i)$(QR0(i) eq 0) = 0;
Q.LO(i)$(Q0(i) eq 0)
= 0;
VR.LO(i,j)$(VR0(i,j) ne 0) = 0.000001;
VM.LO(i,j)$(VM0(i,j) ne 0) = 0.000001;
V.LO(i,j)$(V0(i,j) ne 0)
= 0.000001;
VR.LO(i,j)$(VR0(i,j) eq 0) = 0;
VM.LO(i,j)$(VM0(i,j) eq 0) = 0;
V.LO(i,j)$(V0(i,j) eq 0)
= 0;
The follow statement uses GAMS-Options to reduce the amount of
output and computer time assigned to solve the model. This is not
recommended for beginners who may do better by getting more output from
GAMS. Especially, for those having problems obtaining a “zero error
message”. Iterlim, limrow, lincol and solprint, will limit the number
of iterations, suppress the printing of equations, suppress the
printing of columns, and suppress the list of the solution,
respectively. Although this saves paper, we do not recommend it unless
you understand your model very well and have your model running without
error messages.
OPTIONS ITERLIM=5000, LIMROW=0, LIMCOL=0, SOLPRINT=OFF;
MODEL and SOLVE statements
162
A group
the statement
considered as
give a name to
of equations constitute a mathematical model. GAMS uses
MODEL to allow us to specify which equations should be
part of our mathematical model. In addition, we need to
our model, i.e.; our Model is called OKLAHOMA.
*-- MODEL DEFINITION AND SOLVE STATEMENT
MODEL OKLAHOMA /ALL/;
We use in our example all the declared equations, if that would
not be the case, instead of the word “ALL” we would have written each
equation needed.
Equilibrium is found by minimizing the objective function EQZ
that calculates the absolute sum of deviations (Slack variables). This
process was introduced in section 4.2. {Click here to review section
4.2} The GAMS-statement to solve the mathematical program defined by
the model OKLAHOMA with objective Z, using the MINOS5 non-linear
programming algorithm NLP, reads as:
SOLVE OKLAHOMA MINIMIZING Z USING NLP;
REPORTING VALIDATION OF THE MODEL
When an equilibrium solution has been computed, the results are
sorted in tabulation format. We define tables for commodity balances,
prices, consumer budgets, etc.. These tables give the level of the
endogenous variables of OKLAHOMA model. If they are correct, the values
of these tables validate with those of our base year (SAM values). We
call this process the validation of the model.
*-- SOLUTION DISPLAY STATEMENT
*-- SOLUTION VALUES OF ENDOGENOUS VARIABLES
PARAMETER VALID VARIABLES FOR THE VALIDATION OF THE MODEL;
VALID(i,"SLACK1") = SLACK.L(i);
VALID(i,"SLACK2") = SLACK2.L(i);
VALID(i,"PR") = PR.L(i);
VALID(i,"P") = P.L(i);
VALID(i,"PN") = PN.L(i);
VALID(i,"PK") = PK.L(i);
VALID(ag,"PT") = PT.L(ag);
VALID(i,"PX") = PX.L(i);
VALID(i,"PE") = PE0(i);
VALID(i,"X") = X.L(i);
VALID(i,"R") = R.L(i);
VALID(i,"EXP") =EXP.L(i);
VALID(i,"M") = M.L(i);
VALID(i,"VA") = VA.L(i);
VALID(i,"LAB") =LAB.L(i);
VALID(i,"CAP") =CAP.L(i);
VALID(ag,"LAND") =LAND.L(ag);
VALID(i,"TVR") =TVR.L(i);
VALID(i,"TVM") =TVM.L(i);
VALID(i,"TV") =TV.L(i);
VALID(i,"Q") =Q.L(i);
VALID(i,"QR") =QR.L(i);
163
VALID(i,"QM") =QM.L(i);
VALID(i,"QGOV") =QGOV.L(i);
VALID(i,"QGOVR") =QGOVR.L(i);
VALID(i,"QGOVM") =QGOVM.L(i);
VALID(i,"QINV") =QINV.L(i);
VALID(i,"QINVR") =QINVR.L(i);
VALID(i,"QINVM") =QINVM.L(i);
PARAMETER VALID2 -INTERMEDIATE USE MATRIX-;
VALID2(I,"AGR","V")=V.L(I,"AGR");
VALID2(I,"MIN","V")=V.L(I,"MIN");
VALID2(I,"MAN","V")=V.L(I,"MAN");
VALID2(I,"SER","V")=V.L(I,"SER");
VALID2(I,"AGR","VR")=VR.L(I,"AGR");
VALID2(I,"MIN","VR")=VR.L(I,"MIN");
VALID2(I,"MAN","VR")=VR.L(I,"MAN");
VALID2(I,"SER","VR")=VR.L(I,"SER");
VALID2(I,"AGR","VM")=VM.L(I,"AGR");
VALID2(I,"MIN","VM")=VM.L(I,"MIN");
VALID2(I,"MAN","VM")=VM.L(I,"MAN");
VALID2(I,"SER","VM")=VM.L(I,"SER");
PARAMETER VALID3 -VALIDATION OF THE MODEL-;
VALID3("OBJECTIVE") = Z.L;
VALID3("PL") = PL.L;
VALID3("LMIG")=LMIG.L;
VALID3("KMIG")=KMIG.L;
VALID3("TCAP")=TCAP.L;
VALID3("TLAB")=TLAB.L;
VALID3("LS")=LS.L;
VALID3("LMIG")=LMIG.L;
VALID3("ADJL") = ADJL.L;
VALID3("LY")=LY.L;
VALID3("ALY")=ALY.L;
VALID3("KY")=KY.L;
VALID3("TY")=TY.L;
VALID3("YENT") = YENT.L;
VALID3("RETENT")=RETENT.L;
VALID3("YH")=YH.L;
VALID3("PL") = PL.L;
VALID3("DYH")=DYH.L;
VALID3("HSAV")=HSAV.L;
VALID3("SAV")=SAV.L;
VALID3("INV") = INV.L;
VALID3("YGOV")=YGOV.L;
VALID3("GOVEXP")=GOVEXP.L;
VALID3("IBTX")=IBTX.L;
VALID3("GRP")=GRP.L;
VALID3("AHEMP")=AHEXP.L;
option decimals=3;
DISPLAY VALID,VALID2,VALID3;
SIMULATION
Before starting a simulation run, one should specify the name of
the scenario (here, simul1). The last step in preparing the model is to
define the index sets and parameters for reporting. We define postequilibrium variables that we use in constructing indexes for the
relevant variables.
*######## SIMULATION ############*
164
PE0(i)=1.1;
model simul1 /all/;
solve simul1 minimizing z using nlp;
OPTION SOLPRINT=OFF;
*-- SOLUTION DISPLAY STATEMENT
*-- SOLUTION VALUES OF ENDOGENOUS VARIABLES
PARAMETER PRICES MARKET CLEARING PRICES;
PRICES(i,"SLACK1") = SLACK.L(i);
PRICES(i,"SLACK2") = SLACK2.L(i);
PRICES(i,"PR") = PR.L(i);
PRICES(i,"P") = P.L(i);
PRICES(i,"PN") = PN.L(i);
PRICES(i,"PK") = PK.L(i);
PRICES(ag,"PT") = PT.L(ag);
PRICES(i,"PX") = PX.L(i);
PRICES(i,"PE") = PE0(i);
PARAMETER PROD1 MARKET CLEARING PRODUCTION VARIABLES;
PROD1(i,"X") = X.L(i);
PROD1(i,"R") = R.L(i);
PROD1(i,"EXP") =EXP.L(i);
PROD1(i,"M") = M.L(i);
PROD1(i,"VA") = VA.L(i);
PROD1(i,"LAB") =LAB.L(i);
PROD1(i,"CAP") =CAP.L(i);
PROD1(ag,"LAND") =LAND.L(ag);
PARAMETER TRADE1 MARKET CLEARING PRODUCTION VARIABLES;
TRADE1(i,"TVR") =TVR.L(i);
TRADE1(i,"TVM") =TVM.L(i);
TRADE1(i,"TV") =TV.L(i);
TRADE1(i,"Q") =Q.L(i);
TRADE1(i,"QR") =QR.L(i);
TRADE1(i,"QM") =QM.L(i);
TRADE1(i,"QGOV") =QGOV.L(i);
TRADE1(i,"QGOVR") =QGOVR.L(i);
TRADE1(i,"QGOVM") =QGOVM.L(i);
TRADE1(i,"QINV") =QINV.L(i);
TRADE1(i,"QINVR") =QINVR.L(i);
TRADE1(i,"QINVM") =QINVM.L(i);
PARAMETER PRODUCT2 -PRODUCTION SYSTEMS VARIABLES-;
PRODUCT2(I,"AGR","V")=V.L(I,"AGR");
PRODUCT2(I,"MIN","V")=V.L(I,"MIN");
PRODUCT2(I,"MAN","V")=V.L(I,"MAN");
PRODUCT2(I,"SER","V")=V.L(I,"SER");
PRODUCT2(I,"AGR","VR")=VR.L(I,"AGR");
PRODUCT2(I,"MIN","VR")=VR.L(I,"MIN");
PRODUCT2(I,"MAN","VR")=VR.L(I,"MAN");
PRODUCT2(I,"SER","VR")=VR.L(I,"SER");
PRODUCT2(I,"AGR","VM")=VM.L(I,"AGR");
PRODUCT2(I,"MIN","VM")=VM.L(I,"MIN");
PRODUCT2(I,"MAN","VM")=VM.L(I,"MAN");
PRODUCT2(I,"SER","VM")=VM.L(I,"SER");
PARAMETER OTHER1 MARKET CLEARING VALEUES OF VARIABLES;
OTHER1("OBJECTIVE") = Z.L;
OTHER1("PL") = PL.L;
OTHER1("LMIG")=LMIG.L;
OTHER1("KMIG")=KMIG.L;
OTHER1("TCAP")=TCAP.L;
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OTHER1("TLAB")=TLAB.L;
OTHER1("LS")=LS.L;
OTHER1("LMIG")=LMIG.L;
OTHER1("ADJL") = ADJL.L;
OTHER1("LY")=LY.L;
OTHER1("ALY")=ALY.L;
OTHER1("KY")=KY.L;
OTHER1("TY")=TY.L;
OTHER1("YENT") = YENT.L;
OTHER1("RETENT")=RETENT.L;
OTHER1("YH")=YH.L;
OTHER1("PL") = PL.L;
OTHER1("DYH")=DYH.L;
OTHER1("HSAV")=HSAV.L;
OTHER1("SAV")=SAV.L;
OTHER1("INV") = INV.L;
OTHER1("YGOV")=YGOV.L;
OTHER1("GOVEXP")=GOVEXP.L;
OTHER1("IBTX")=IBTX.L;
OTHER1("GRP")=GRP.L;
OTHER1("AHEMP")=AHEXP.L;
option decimals=3;
DISPLAY PROD1, TRADE1,PRODUCT2;
OPTION DECIMALS = 8;
DISPLAY OTHER1, PRICES;
* Parameters AS INDEX WITH 1993=1.000
PARAMETERS
* -- Price block
IPL
Wage rate index
IPK(i)
Rent to capital index
IPT(ag)
Land rent index
IPR(i)
Regional price index
IP(i)
Composite price index
IPG
General composite price index
* -- Production block
IL(i)
Labor demand index
ITL
Total labor demand index
ILS
Labor supply index
IK(i)
capital demand index
ITK
Total Capital use index
ITT
Total Land use index
IT(ag)
Land demand index
IVA(i)
Value added index
IX(i)
Output index
ITVA
Total Value added index
ITX
Total Output index
ITE
Total Export index
ITR
Total Reg. supply index
ITM
Total Import index
IVM(j,i)
Imported interm demand index
IVR(j,i)
Regional interm demand index
IR(i)
Regional supply index
IE(i)
Export index
IM(i)
Import index
* -- Income block
IYH
YHch
IDYH
Household (in the region) income index
Change in hh income
Disposable income index
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IHSAV
Household saving index
IYGOV
Government revenue index
NETGOV
Net Revenue for government
IGRP
Gross region product index
GRPch
Change in Gross regional product
CapComp
Capital Compensation
LandComp
Land Compensation
Rconsup
Resident angler consumer surplus loss
NRconsup
NonResident angler consumer surplus loss
* -- Expenditure block
IAHEXP
adj. Household expenditure index
IGOVEXP
Government expenditure index
IQ(i)
Commodity demand index
IQM(i)
Imported commodity demand index
IQR(i)
Regional commodity demand index
;
*-- EQUATIONS FOR CALCULATION OF INDEX WITH 1993=1.000
*### Price block
IPL
= PL.L/PL0;
IPK(i)
= PK.L(i)/PK0(i);
IPT(ag) = PT.L(ag)/PT0(ag);
IPR(i)
= PR.L(i)/PR0(i);
IP(i)
= P.L(i)/P0(i);
IPG
(PR.L(i)*R0(i)+PM0(i)*M0(i))/(R0(i)+M0(i)))/4;
*#* Production block
IL(i)
= LAB.L(i)/L0(i);
ITL
= (Sum(i,LAB.L(i))+(LHHH0+LGOV0))
/(Sum(i,L0(i))+LHHH0+LGOV0);
ILS
= LS.L /LS0 ;
IK(i)
= CAP.L(i)/K0(i);
ITK
= Sum(i,PK.L(i)*CAP.L(i))/Sum(i,K0(i));
IT("Agr") = LAND.L("Agr")/T0("Agr");
ITT
= PT.L("Agr")*LAND.L("Agr")/T0("Agr");
IVA(i)
= VA.L(i)/Va0(i);
ITVA
= Sum(i,VA.L(i))/Sum(i,Va0(i));
IX(i)
= X.L(i)/X0(i);
ITX
=Sum(i,X.L(i))/Sum(i,X0(i));
ITR
=Sum(i,R.L(i))/Sum(i,R0(i));
ITM
=Sum(i,M.L(i))/Sum(i,M0(i));
IVM(j,i)= VM.L(j,i)/VM0(j,i);
IVR(j,i)= VR.L(j,i)/VR0(j,i);
IR(i)
= R.L(i)/R0(i);
IE(i)
= EXP.L(i)/E0(i);
ITE
=Sum(i,EXP.L(i))/Sum(i,E0(i));
*## Income block
IYH
= YH.L /YH0 ;
IDYH
= DYH.L /DYH0 ;
IHSAV
= HSAV.L /HSAV0 ;
IGRP
= GRP.L/GRP0;
GRPch
= GRP.L-GRP0;
*#Expenditure block
IAHEXP
= AHEXP.L /HEXP0 ;
IQ(i)
= Q.L(i)/Q0(i);
IQM(i)
= QM.L(i)/QM0(i);
IQR(i)
= QR.L(i)/QR0(i);
IM(i)
= M.L(i)/M0(i);
YHch
= YH.L -adjL.L*YH0 ;
IYGOV
= YGOV.L/YGOV0;
IGOVEXP
= GOVEXP.L/GOVEXP0;
NETGOV
= YGOV.L-GOVEXP.L;
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=SUM(i,
*##- SOLUTION VALUES OF INDEX
option decimals=5;
PARAMETER INDEX INDEXES FOR THE SIMULATION;
INDEX(I,"IPR")=IPR(I);
INDEX(I,"IX")=IX(I);
INDEX(I,"IE")=IE(I);
INDEX(I,"IL")=IL(I);
INDEX(I,"IK")=IK(I);
INDEX(I,"IPK")=IPK(I);
INDEX(ag,"IPT")=IPT(ag);
INDEX(ag,"IT")=IT(ag);
INDEX(I,"IVA")=IVA(I);
INDEX(I,"IR")=IR(I);
INDEX(I,"IM")=IM(I);
INDEX(I,"IQ")=IQ(I);
INDEX(I,"IQR")=IQR(I);
INDEX(I,"IQM")=IQM(I);
INDEX(I,"IPR")=IPR(I);
INDEX(I,"IPR")=IPR(I);
DISPLAY INDEX;
DISPLAY ITX,ITE,ITL,IPL,
ITK,ITT,
IGRP,GRPch,ITVA,ITR,ITM, YHch,
IYH, IYGOV,IGOVEXP,NETGOV,
ILS,IDYH,IHSAV,IAHEXP,
IVM,IVR;
DISPLAY IGRP,IPG,IYH,ITE,ITM;
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