Equilibrium Heterogeneous-Agent models as measurement tools: Some Monte Carlo evidence

This paper discusses a series of Monte Carlo experiments designed to evaluate the empirical properties of Heterogeneous-Agent macroeconomic models in the presence of sampling variability. The calibration procedure leads to the welfare analysis being conducted with the wrong parameters. The ability of the calibrated model to correctly predict the long-run welfare changes induced by a set of policy experiments is assessed. The results show that, for the policy reforms with sizable welfare effects (i.e., more than 0.2%), the model always predicts the right sign of the welfare effects. However, the welfare effects can be evaluated with the wrong sign, when they are small and when the sample size is fairly limited. Quantitatively, the maximum errors made in evaluating a policy change are very small for some reforms (in the order of 0.02 percentage points), but bigger for others (in the order of 0.6 percentage points). Finally, having access to better data, in terms of larger samples, does lead to substantial increases in the precision of the welfare effects estimates, though the rate of convergence can be slow.     

EVALUATING SUPPLY-SIDE AND DEMAND-SIDE SHOCKS FOR FISHERIES: A COMPUTABLE GENERAL EQUILIBRIUM (CGE) MODEL FOR ALASKA

This study used computable general equilibrium (CGE) models to investigate the economic effects of three exogenous shocks to Alaska fisheries: (1) reduction in pollock allowable catch (TAC); (2) increase in fuel price; and (3) reduction in demand for seafood. Two different model versions, ‘Keynesian’ and ‘neoclassical’, were used to estimate impacts on endogenous output, employment, value added, and household income. By using a CGE model, this study overcomes the limitations of fixed-price models (such as input–output models) including (1) inability to calculate welfare effects due to fixed prices; and (2) difficulty of addressing supply-side shocks. There are currently few examples of CGE studies addressing fisheries issues appearing in the literature. Among those, this study is unique in that it uses a relatively disaggregated sector scheme and examines both supply-side and demand-side shocks.     

On the welfare costs of business-cycle fluctuations and economic-growth variation in the 20th century and beyond

The main objective of this paper is to propose a novel setup that allows estimating separately the welfare costs of the uncertainty stemming from business-cycle fluctuations and from economic-growth variation, when the two types of shocks associated with them (respectively, transitory and permanent shocks) hit consumption simultaneously. Separating these welfare costs requires dealing with degenerate bivariate distributions. Levi's Continuity Theorem and the Disintegration Theorem allow us to adequately define the one-dimensional limiting marginal distributions. Under Normality, we show that the parameters of the original marginal distributions are not affected, providing the means for calculating separately the welfare costs of business-cycle fluctuations and of economic-growth variation.Our empirical results show that, if we consider only transitory shocks, the welfare cost of business cycles is much smaller than previously thought. Indeed, we found it to be negative – −0.03% of per-capita consumption! On the other hand, we found that the welfare cost of economic-growth variation is relatively large. Our estimate for reasonable preference-parameter values shows that it is 0.71% of consumption – US$ 208.98 per person, per year.     

Applicability of a spatial computable general equilibrium model to assess the short-term economic impact of natural disasters

Computable general equilibrium (CGE) models have been widely used to assess the economic impact of natural disasters, but the models have not been fully validated by applying them to real disasters. This study focuses on validating a model for use in a short-run case in which the functional recovery of infrastructure and businesses occurred on a time scale of a few months. A special attempt is made to determine the parameter values of elasticity of substitutions, which play an important role in the effect on supply chains. In this study, a spatial CGE model, in which Japan is divided into nine regions, is constructed and applied to the case of the 2011 Great East Japan Earthquake and Tsunami. Through this application, the best estimates of the elasticity parameters generated relatively consistent estimates of production change compared with the observed change, both in severely affected regions and in other regions.     

CONTRIBUTIONS OF THE GATT/WTO TO GLOBAL ECONOMIC WELFARE: EMPIRICAL EVIDENCE

This paper surveys estimates of the value of the GATT/WTO's contributions to global welfare through providing a forum for negotiating reductions in policy‐induced distortions to trade flows, including through the process of accession by new members. After reviewing measures of the price‐distorting effects of trade‐related policies, it assesses estimates from global simulation models of the welfare effects of trade liberalizations prior to the WTO's Doha round, including the net benefits and transfers associated with implementing the Uruguay Round agreement on trade‐related intellectual property rights, and then reviews estimates of the potential welfare effects of a Doha round agreement to cut tariffs and subsidies. Econometric estimates of past trade and related effects of the GATT/WTO are then examined, before turning to estimates of the benefits of WTO accession and of potential benefits from WTO‐sponsored trade facilitation. The paper concludes that while it remains difficult to attribute reforms directly to the GATT/WTO, the overall body of evidence presented supports the economic profession's consensus that this institution has contributed substantially to global economic welfare.     

Economic consequences of intifada

In 2003 the World Bank (WB) and the International Monetary Fund (IMF) published estimates of macro-economic indicators for 2002 of the economy of Palestine. The WB used a micro-founded recursive dynamic computable general equilibrium (CGE) model, calibrated on the 1998 Social Accounting Matrix (SAM) of Palestine, to which shocks were applied, whereas the IMF based its estimates on a macro-founded income-expenditure model relying on more recent data. It turned out that there were substantial differences: the estimate by the WB of the real gross national income (at 1998 prices) was 25% less than the corresponding figure calculated by the IMF. This huge difference is not only relevant for a full understanding of the economic consequences of the intifada, but also for the size of the international community intervention. In this paper we propose our own evaluation with the help of a static CGE model, based on the 1998 SAM and the so-called intifada shock derived from data of the WB that we constructed for the analysis of some forms of emergency assistance in a previous article. It turns out that our estimates, based on an entirely different methodology, are remarkably close to those of the IMF.     

VARs,common factors and the empirical validation of equilibrium business cycle models

Equilibrium business cycle models have typically less shocks than variables. As pointed out by Altug (1989) International Economic Review 30 (4) 889–920 and Sargent (1989) The Journal of Political Economy 97 (2) 251–287, if variables are measured with error, this characteristic implies that the model solution for measured variables has a factor structure. This paper compares estimation performance for the impulse response coefficients based on a VAR approximation to this class of models and an estimation method that explicitly takes into account the restrictions implied by the factor structure. Bias and mean-squared error for both factor- and VAR-based estimates of impulse response functions are quantified using, as data-generating process, a calibrated standard equilibrium business cycle model. We show that, at short horizons, VAR estimates of impulse response functions are less accurate than factor estimates while the two methods perform similarly at medium and long run horizons.     

Consistent factor estimation in dynamic factor models with structural instability

This paper considers the estimation of approximate dynamic factor models when there is temporal instability in the factor loadings. We characterize the type and magnitude of instabilities under which the principal components estimator of the factors is consistent and find that these instabilities can be larger than earlier theoretical calculations suggest. We also discuss implications of our results for the robustness of regressions based on the estimated factors and of estimates of the number of factors in the presence of parameter instability. Simulations calibrated to an empirical application indicate that instability in the factor loadings has a limited impact on estimation of the factor space and diffusion index forecasting, whereas estimation of the number of factors is more substantially affected.     

A discrete-time model for daily S & P500 returns and realized variations: Jumps and leverage effects

We develop an empirically highly accurate discrete-time daily stochastic volatility model that explicitly distinguishes between the jump and continuous-time components of price movements using nonparametric realized variation and Bipower variation measures constructed from high-frequency intraday data. The model setup allows us to directly assess the structural inter-dependencies among the shocks to returns and the two different volatility components. The model estimates suggest that the leverage effect, or asymmetry between returns and volatility, works primarily through the continuous volatility component. The excellent fit of the model makes it an ideal candidate for an easy-to-implement auxiliary model in the context of indirect estimation of empirically more realistic continuous-time jump diffusion and Lévy-driven stochastic volatility models, effectively incorporating the interdaily dependencies inherent in the high-frequency intraday data.     

On the suitability of income inequality measures for regional analysis: Some evidence from simulation analysis and bootstrapping tests

The paper looks at the sensitivity of commonly used income inequality measures to changes in the ranking, size and number of regions into which a country is divided. During the analysis, several test distributions of populations and incomes are compared with a ‘reference’ distribution, characterized by an even distribution of population across regional subdivisions. Random permutation tests are also run to determine whether inequality measures commonly used in regional analysis produce meaningful estimates when applied to regions of different population size. The results show that only the population weighted coefficient of variation (Williamson’s index) and population-weighted Gini coefficient may be considered sufficiently reliable inequality measures, when applied to countries with a small number of regions and with varying population sizes.     

Trade Liberalization and Poverty in Ecuador: A CGE Macro-Microsimulation Analysis

Cross-country analysis of the aggregate growth-poverty link is likely to miss important country-specific detail and possible offsetting forces in the underlying labour market adjustment process. This paper combines a CGE model analysis with a microsimulations approach to analyse the effects of trade liberalization on poverty and income distribution in Ecuador. The CGE model enables us to disentangle the general equilibrium effects of various trade policy scenarios on sector output, employment, factor incomes and household consumption. However, as is typical of CGE models, this analysis only provides distribution results for fairly aggregated groups of workers and a reduced number of representative households. The microsimulations approach adds the full distribution to the analysis and allows simulation of the effects of trade reform on the job status and remuneration of individual workers and thereby on household income distribution and poverty. The macro- microsimulation results indicate that the trade opening in Ecuador induced mild aggregate welfare gains, but rising income inequality due to rising wage differentials between skilled and unskilled workers implies virtually no poverty-reducing effect from trade liberalization.     

ECONOMIC WELFARE ANALYSIS OF THE LEGALIZATION OF DRUGS: A CGE MICROSIMULATION MODEL FOR COLOMBIA

In this paper, a computable general equilibrium (CGE) microsimulation model is used to analyze the effects of an ex ante legalization of drugs on the Colombian economy. The model consists of 11 productive sectors, 3 different labor force categories with unemployment, and 20 households divided by income and location. Changes in wages and migration are estimated using a labor participation model, and a NIDS estimates the demands of the households. Changes in household economic welfare, measured by changes in income and prices (CV and EV measurements), are very sensitive to the reinvestments that the government makes in the economy. By analyzing six different scenarios with different assumptions about changes in drug prices, investments of the government, and the termination of the armed conflict, the results suggest that economic welfare improves when the government reinvests military expenditures in other productive sectors or when the ‘economy of war’ continues and the legalization does not end the armed conflict.     

An Application of an Integrated Transport Network– Multiregional CGE Model: a Framework for the Economic Analysis of Highway Projects

This paper develops a framework for the economic analysis of highway projects that is then used to estimate the dynamic economic effects of a highway project on the economic growth and the regional disparity in Korea. The framework is composed of a transport model and a multiregional Computable General Equilibrium (CGE) model. The transport model measures a change in interregional shortest distances and the accessibility due to the highway project. The CGE model estimates the spatial economic effects of the project on GDP, the price, exports, and the regional distribution of wages and population. The simulation allows policy makers to determine which highway development deserves the priority for investment, based on consideration of economic growth and regional economic equity in the long run. The simulation found that all the highway projects have positive effects on GDP and export growth as well as regional equity in terms of wage and population.     

DOES GOVERNMENT SPENDING AFFECT INCOME INEQUALITY? A META-REGRESSION ANALYSIS

In this paper findings of a meta-regression analysis are presented exploring the effects of government spending on income inequality, with a particular focus on low- and middle-income countries. We identify a total of 84 separate studies containing over 900 estimates of the effect of one or more measures of spending on one or more measures of income inequality. The results show some evidence of a moderate negative relationship between government spending and income inequality, which is strongest for social welfare and other social spending, and when using the Gini coefficient or the top income share as the measure of inequality. However, both the size and direction of the estimated relationship between government spending and income inequality is affected by a range of other factors, including the control variables and estimation method used. We also find evidence of publication bias, in that negative estimates of the relationship appear to be under-reported in the literature.     

Repeat Purchase amid Rapid Quality Improvement: Structural Estimation of Demand for Personal Computers

This paper estimates a structural model of demand for the personal computer (PC) by repeat purchasers. Taking advantage of a large data set on household-level PC purchases, the econometric model uses variation in PC holdings among PC owners to identify households' marginal values of quality improvements. The analysis only requires data on a cross-section of households along with observed PC offerings over time, and accounts for stock effects, forward-looking behavior, and large amounts of household heterogeneity. The estimates allow us to measure sensitivity to long-term and short-term price and technology changes, as well as consumer welfare changes from technological improvements. The results show a large variation in marginal values for PC quality across households, and that failing to account for forward-looking behavior results in biased estimates and a poorer fit to the data. Incorporating stock effects proves especially important because, for the data used here, the model's parameters are not only biased but also virtually impossible to pin down without them. The results also show that price elasticity is approximately 25% higher in the short term compared to the long term, and technology elasticity is approximately 35% higher in the short term compared to the long term. Furthermore, welfare measurements are significantly underestimated when using a model that does not account for forward-looking behavior. Finally, the model is extended to include first-time purchasers. The results show similar patterns, but should be interpreted with much caution owing to the likely presence of significant unobserved heterogeneity between new purchasers and repeat purchasers.     

USING A CGE MODEL TO IDENTIFY THE POLICY TRADE-OFF BETWEEN UNEMPLOYMENT AND INFLATION. THE EFFICIENT PHILLIPS CURVE

This paper provides a new reading of a classical economic relation: the short-run Phillips curve. Our point is that, when dealing with inflation and unemployment, policy-making can be understood as a multicriteria decision-making problem. Hence, we use so-called multiobjective programming in connection with a computable general equilibrium (CGE) model to determine the combinations of policy instruments that provide efficient combinations of inflation and unemployment. This approach results in an alternative version of the Phillips curve labelled as efficient Phillips curve. Our aim is to present an application of CGE models to a new area of research that can be especially useful when addressing policy exercises with real data. We apply our methodological proposal within a particular regional economy, Andalusia, in the south of Spain. This tool can give some keys for policy advice and policy implementation in the fight against unemployment and inflation.     

COMPUTABLE GENERAL EQUILIBRIUM MODELS FOR DEVELOPMENT POLICY ANALYSIS IN LDCs

Abstract. The use of CGE models has gained much popularity among policy analysts in LDCs and there is a fast growing body of literature on this area of economics. In this survey, the advantages of general equilibrium approach over partial equilibrium approach in analysing a wide range of policy issues are highlighted. The evolution of CGE modelling is discussed and more than 60 CGE applications related to different policy issues in LDCs are surveyed. This comprehensive survey shows that the CGE models have become quite popular analytical tools among policy analysts in LDCs over the last decade or so. The debate in the economic profession regarding the value and appropriateness of using CGE models for policy analysis is examined in the final section of this paper. Some of the criticisms levelled at CGE models are discussed and it is argued that despite this criticism such models are capable of providing insight into important policy problems.     

Threshold bipower variation and the impact of jumps on volatility forecasting

This study reconsiders the role of jumps for volatility forecasting by showing that jumps have a positive and mostly significant impact on future volatility. This result becomes apparent once volatility is separated into its continuous and discontinuous components using estimators which are not only consistent, but also scarcely plagued by small sample bias. With the aim of achieving this, we introduce the concept of threshold bipower variation, which is based on the joint use of bipower variation and threshold estimation. We show that its generalization (threshold multipower variation) admits a feasible central limit theorem in the presence of jumps and provides less biased estimates, with respect to the standard multipower variation, of the continuous quadratic variation in finite samples. We further provide a new test for jump detection which has substantially more power than tests based on multipower variation. Empirical analysis (on the S&P500 index, individual stocks and US bond yields) shows that the proposed techniques improve significantly the accuracy of volatility forecasts especially in periods following the occurrence of a jump.     

Modeling conflict impact and postconflict reconstruction: The case of Yemen

Evidence-based planning for countries in the midst of conflict is often constrained by missing data and the lack of appropriate analytical tools. To overcome these constraints, we use a computable general equilibrium (CGE) model combined with systematic sensitivity analysis (SSA) to investigate the impact of conflict on Yemen’s economy and to analyze potential pathways for recovery after the conflict finally ends. Our results suggest that conflict-related disruptions in agriculture and mining sent devastating shockwaves throughout the economy, accounting for the lion’s share of the country’s economic losses and increase in poverty. Our results suggest that supporting agriculture should take the highest priority, as reconstruction of that sector, followed by the mining sector, has the largest positive impact on growth and poverty reduction. However, our estimates also suggest that the restoration of its prewar economic status quo is unlikely. In addition to serving as a direct input for Yemen’s reconstruction planning, our paper also demonstrates the usefulness of overarching models for conflict and postconflict economic assessments.     

不同征地补偿模式下失地农民福利变化研究——来自准自然实验模糊评价的证据

本文借助森的可行能力理论框架,利用模糊评价方法,采用准自然实验思路,试图比较不同的征地补偿模式对农民福利水平的影响,并得出结论:农民被征地后的福利水平较之前略有提高,但总体福利水平仍然较低.虽然土地换社保的补偿模式在保障失地农民收入水平方面不如土地换货币模式,但是前者给予农民更健全的社会保障制度,从而使农民获得更高的福利水平.