Pub Date : 2015-02-20DOI: 10.21642/JGEA.010101SM1F
P. Dixon, M. Jerie, Maureen T. Rimmer
This paper is for CGE modelers and others interested in modern trade theory. The Armington specification of trade, assuming country-level product differentiation, has been central to CGE modelling for 40 years. Starting in the 1980s with Krugman and more recently Melitz, trade theorists have preferred specifications with firm-level product differentiation. We draw out the connections between the Armington, Krugman and Melitz models, deriving them as successively less restrictive special cases of an encompassing model. We then investigate optimality properties of the Melitz model, demonstrating that a Melitz general equilibrium is the solution to a global, cost-minimizing problem. This suggests that envelope theorems can be used in interpreting results from a Melitz model. Next we explain the Balistreri-Rutherford decomposition in which a Melitz general equilibrium model is broken into Melitz sectoral models combined with an Armington general equilibrium model. Balistreri and Rutherford see their decomposition as a basis of an iterative approach for solving Melitz general equilibrium models. We see it as a means for interpreting Melitz results as the outcome of an Armington simulation with additional shocks to productivity and preferences variables. With CGE modelers in mind, we report computational experience in solving a Melitz general equilibrium model using GEMPACK. Key words: Armington, Krugman and Melitz; CGE modelling; international trade. JEL codes: F12; D40; D58; C6
{"title":"Modern Trade Theory for CGE Modelling: the Armington, Krugman and Melitz Models","authors":"P. Dixon, M. Jerie, Maureen T. Rimmer","doi":"10.21642/JGEA.010101SM1F","DOIUrl":"https://doi.org/10.21642/JGEA.010101SM1F","url":null,"abstract":"This paper is for CGE modelers and others interested in modern trade theory. The Armington specification of trade, assuming country-level product differentiation, has been central to CGE modelling for 40 years. Starting in the 1980s with Krugman and more recently Melitz, trade theorists have preferred specifications with firm-level product differentiation. We draw out the connections between the Armington, Krugman and Melitz models, deriving them as successively less restrictive special cases of an encompassing model. We then investigate optimality properties of the Melitz model, demonstrating that a Melitz general equilibrium is the solution to a global, cost-minimizing problem. This suggests that envelope theorems can be used in interpreting results from a Melitz model. Next we explain the Balistreri-Rutherford decomposition in which a Melitz general equilibrium model is broken into Melitz sectoral models combined with an Armington general equilibrium model. Balistreri and Rutherford see their decomposition as a basis of an iterative approach for solving Melitz general equilibrium models. We see it as a means for interpreting Melitz results as the outcome of an Armington simulation with additional shocks to productivity and preferences variables. With CGE modelers in mind, we report computational experience in solving a Melitz general equilibrium model using GEMPACK. Key words: Armington, Krugman and Melitz; CGE modelling; international trade. JEL codes: F12; D40; D58; C6","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"25 6","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120873310","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The EU Single Farm Payment (SFP) is currently distributed in proportion to primary factor shares in version 8 of the GTAP database. In this paper, we investigate whether this way of modeling the EU SFP makes a difference in analyzing agricultural policy reforms. To do so, we create alternative versions of the GTAP database to compare the effects with the default setting in GTAP. Employing OECD data, along with the GTAP framework, we vary the assumptions about the allocation of the SFP. In the process, we demonstrate how to alter and update the GTAP database to implement domestic support of OECD PSE tables. We provide a detailed overview supplemented with assumptions of payment allocation, shock calculations and in particular, the Altertax procedure to update value flows and price equations extended in the GTAP model. Subsequently, we illustrate the impact of those assumptions by simulating a 100% removal of the SFP using the deviating versions of GTAP database. This sensitivity analysis reveals strong differences in results, but particularly in production responses of food and agricultural sectors that decrease with an increasing degree of decoupling. Furthermore, our analysis shows that the effect on welfare and the trade balance decreases with an increasing degree of decoupling. This experiment shows that the allocation of the SFP can have strong impacts on simulation results.
{"title":"Extending the GTAP Data Base and Model to Cover Domestic Support Issues using the EU as Example","authors":"Kirsten Urban, H. Jensen, M. Brockmeier","doi":"10.21642/gtap.tp35","DOIUrl":"https://doi.org/10.21642/gtap.tp35","url":null,"abstract":"The EU Single Farm Payment (SFP) is currently distributed in proportion to primary factor shares in version 8 of the GTAP database. In this paper, we investigate whether this way of modeling the EU SFP makes a difference in analyzing agricultural policy reforms. To do so, we create alternative versions of the GTAP database to compare the effects with the default setting in GTAP. Employing OECD data, along with the GTAP framework, we vary the assumptions about the allocation of the SFP. In the process, we demonstrate how to alter and update the GTAP database to implement domestic support of OECD PSE tables. We provide a detailed overview supplemented with assumptions of payment allocation, shock calculations and in particular, the Altertax procedure to update value flows and price equations extended in the GTAP model. Subsequently, we illustrate the impact of those assumptions by simulating a 100% removal of the SFP using the deviating versions of GTAP database. This sensitivity analysis reveals strong differences in results, but particularly in production responses of food and agricultural sectors that decrease with an increasing degree of decoupling. Furthermore, our analysis shows that the effect on welfare and the trade balance decreases with an increasing degree of decoupling. This experiment shows that the allocation of the SFP can have strong impacts on simulation results.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"199 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124383081","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We synthesized a range of geographically-explicit forest, grassland and cropland biomass and soil carbon input data sources and used geographic information systems (GIS) software to calculate new estimates of soil and biomass carbon stocks for use with global economic models, particularly for the Global Trade and Analysis Project (GTAP). Our results quantify the average amount of carbon stored in soil and biomass in each of the 246 countries, stratified by agro-ecological zones (available in the accompanying spreadsheet). We also provide the data aggregated to the 134 regions defined for the GTAP 8.1 database both in spreadsheet form and in GTAP’s native binary file format. Finally, we provide an add-on to FlexAgg2 program to further aggregate the 134 regions as desired. Our analysis makes substantial refinements to the estimates of carbon stocks used for modeling carbon emissions from indirect land use change. The spatial detail of our analysis is a major advantage over previous databases because it provides estimates tailored to the regions of interest and better accounts for the variation of carbon stocks across the landscape, and between wetland and non-wetland regions.
{"title":"New Estimates of Soil and Biomass Carbon Stocks for Global Economic Models","authors":"H. Gibbs, S. Yui, R. Plevin","doi":"10.22004/AG.ECON.283432","DOIUrl":"https://doi.org/10.22004/AG.ECON.283432","url":null,"abstract":"We synthesized a range of geographically-explicit forest, grassland and cropland biomass and soil carbon input data sources and used geographic information systems (GIS) software to calculate new estimates of soil and biomass carbon stocks for use with global economic models, particularly for the Global Trade and Analysis Project (GTAP). Our results quantify the average amount of carbon stored in soil and biomass in each of the 246 countries, stratified by agro-ecological zones (available in the accompanying spreadsheet). We also provide the data aggregated to the 134 regions defined for the GTAP 8.1 database both in spreadsheet form and in GTAP’s native binary file format. Finally, we provide an add-on to FlexAgg2 program to further aggregate the 134 regions as desired. Our analysis makes substantial refinements to the estimates of carbon stocks used for modeling carbon emissions from indirect land use change. The spatial detail of our analysis is a major advantage over previous databases because it provides estimates tailored to the regions of interest and better accounts for the variation of carbon stocks across the landscape, and between wetland and non-wetland regions.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126340824","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The purpose of the agro-ecological zone emission factor model (AEZ-EF) is to estimate the total CO2-equivalent emissions from land use changes, e.g., from an analysis of biofuels impacts or policy analyses such as estimating the effect of changes in agricultural productivity on emissions from land use. The model combines matrices of carbon fluxes (Mg CO2/ha/y) with matrices of changes in land use (ha) according to land-use category as projected by GTAP or similar AEZ-oriented models. As published, AEZ-EF aggregates the carbon flows to the same 19 regions and 18 AEZs used by GTAP-BIO, the version of GTAP currently used by Purdue University researchers for modeling biofuel-induced ("indirect") land-use change (ILUC) (e.g., Tyner, Taheripour et al. 2010). The AEZ-EF model, however, is designed to work with an arbitrary number of regions, as described in the accompanying report.
{"title":"Agro-ecological Zone Emission Factor (AEZ-EF) Model (v47)","authors":"R. Plevin, H. Gibbs, J. Duffy, S. Yui, S. Yeh","doi":"10.21642/gtap.tp34","DOIUrl":"https://doi.org/10.21642/gtap.tp34","url":null,"abstract":"The purpose of the agro-ecological zone emission factor model (AEZ-EF) is to estimate the total CO2-equivalent emissions from land use changes, e.g., from an analysis of biofuels impacts or policy analyses such as estimating the effect of changes in agricultural productivity on emissions from land use. The model combines matrices of carbon fluxes (Mg CO2/ha/y) with matrices of changes in land use (ha) according to land-use category as projected by GTAP or similar AEZ-oriented models. As published, AEZ-EF aggregates the carbon flows to the same 19 regions and 18 AEZs used by GTAP-BIO, the version of GTAP currently used by Purdue University researchers for modeling biofuel-induced (\"indirect\") land-use change (ILUC) (e.g., Tyner, Taheripour et al. 2010). The AEZ-EF model, however, is designed to work with an arbitrary number of regions, as described in the accompanying report.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131256117","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper documents GDyn-E CGE model developed for analysis of climate policies in dynamic GTAP framework. Description of the modeling framework is followed by a presentation of a simple application focused on emission leakage associated with a unilateral GHG abatement policy, analysis and decomposition of the emission leakage, and sensitivity analysis.
{"title":"Analysis of Climate Policies with GDyn-E","authors":"A. Golub","doi":"10.21642/gtap.tp32","DOIUrl":"https://doi.org/10.21642/gtap.tp32","url":null,"abstract":"This paper documents GDyn-E CGE model developed for analysis of climate policies in dynamic GTAP framework. Description of the modeling framework is followed by a presentation of a simple application focused on emission leakage associated with a unilateral GHG abatement policy, analysis and decomposition of the emission leakage, and sensitivity analysis.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-10-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122465950","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The goal of this technical paper is to provide sufficient detail to permit readers to bring into the GTAP poverty framework additional countries for which suitable household data are available. With the inputs from processed household data – as per the guidelines provided here – the poverty framework can be readily used to assess the likely poverty impacts of global economic policies across a wide range of developing countries, in a fashion which enables systematic cross-country comparisons.
{"title":"GTAP-POV: A Framework for Assessing the National Poverty Impacts of Global Economic and Environmental Policies","authors":"T. Hertel, M. Verma, M. Ivanic, A. Rios","doi":"10.18235/0000178","DOIUrl":"https://doi.org/10.18235/0000178","url":null,"abstract":"The goal of this technical paper is to provide sufficient detail to permit readers to bring into the GTAP poverty framework additional countries for which suitable household data are available. With the inputs from processed household data – as per the guidelines provided here – the poverty framework can be readily used to assess the likely poverty impacts of global economic policies across a wide range of developing countries, in a fashion which enables systematic cross-country comparisons.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134415614","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
We show how you can carry out systematic sensitivity analysis (SSA) with respect to parameters and/or shocks, which vary according to a specified covariance matrix. You can use the existing SSA tools in RunGTAP or RunGEM to do this if your model is implemented in GEMPACK. Those SSA tools assume that all parameters or shocks are varying independently (i.e., the distributions of all parameters or shocks are uncorrelated) or together (i.e., are completely correlated). The techniques in this paper remove those restrictions. However, users need to make small modifications to the TAB file for the model. Different modifications are needed for different SSA scenarios. Further, the standard SSA procedure built into RunGTAP and RunGEM allows you to compute the sensitivity of model results either with respect to variations in parameter values or with respect to variations in shock values, but you cannot vary both parameters and shocks at the same time. Our discussion concentrates on the parameter case. However, we later show how shock variation may be modelled as a type of parameter variation. This opens the door to simultaneous variation of shocks and parameters. We include worked examples of the techniques described, based on the standard GTAP Model.
{"title":"Systematic Sensitivity Analysis with Respect to Correlated Variations in Parameters and Shocks","authors":"Mark Horridge, K. Pearson","doi":"10.21642/gtap.tp30","DOIUrl":"https://doi.org/10.21642/gtap.tp30","url":null,"abstract":"We show how you can carry out systematic sensitivity analysis (SSA) with respect to parameters and/or shocks, which vary according to a specified covariance matrix. You can use the existing SSA tools in RunGTAP or RunGEM to do this if your model is implemented in GEMPACK. Those SSA tools assume that all parameters or shocks are varying independently (i.e., the distributions of all parameters or shocks are uncorrelated) or together (i.e., are completely correlated). The techniques in this paper remove those restrictions. However, users need to make small modifications to the TAB file for the model. Different modifications are needed for different SSA scenarios. Further, the standard SSA procedure built into RunGTAP and RunGEM allows you to compute the sensitivity of model results either with respect to variations in parameter values or with respect to variations in shock values, but you cannot vary both parameters and shocks at the same time. Our discussion concentrates on the parameter case. However, we later show how shock variation may be modelled as a type of parameter variation. This opens the door to simultaneous variation of shocks and parameters. We include worked examples of the techniques described, based on the standard GTAP Model.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-03-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127619998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
CGE models are utilized for the evaluation of trade policy reforms, yet they are typically highly aggregated, limiting their usefulness to trade negotiators interested in impacts at the tariff line. Partial Equilibrium (PE) models used for disaggregate analysis lack the benefits of an economy-wide analysis required to examine the overall impact of trade policy reforms. This suggests the need for a PE-GE, nested modeling framework to support trade policy analysis. In this paper, we develop a PE model that captures international trade, domestic consumption and output, using CET and CES structures, market clearing conditions and price linkages, nested within the standard GTAP Model. In addition, we extend the welfare decomposition of Huff and Hertel (2001) to this PE-GE model to contrast the sources of welfare gain among models. To illustrate the value-added of this model, we examine the impact of multi-lateral tariff liberalization on the Indian economy, with special focus on the auto sector, using PE, GE and PE-GE models. The PE model does not predict the change in overall size and price level for the industry well, while the GE model underestimates the aggregate welfare gain due to tariff averaging. It also fails to account for the change in industry composition resulting from trade reform. These findings are robust to wide variation in model parameters. We conclude that the linked model is superior to both the GE and PE counterparts.
{"title":"Linking Partial and General Equilibrium Models: A GTAP Application Using TASTE","authors":"B. Narayanan, T. Hertel, Mark Horridge","doi":"10.22004/AG.ECON.283427","DOIUrl":"https://doi.org/10.22004/AG.ECON.283427","url":null,"abstract":"CGE models are utilized for the evaluation of trade policy reforms, yet they are typically highly aggregated, limiting their usefulness to trade negotiators interested in impacts at the tariff line. Partial Equilibrium (PE) models used for disaggregate analysis lack the benefits of an economy-wide analysis required to examine the overall impact of trade policy reforms. This suggests the need for a PE-GE, nested modeling framework to support trade policy analysis. In this paper, we develop a PE model that captures international trade, domestic consumption and output, using CET and CES structures, market clearing conditions and price linkages, nested within the standard GTAP Model. In addition, we extend the welfare decomposition of Huff and Hertel (2001) to this PE-GE model to contrast the sources of welfare gain among models. To illustrate the value-added of this model, we examine the impact of multi-lateral tariff liberalization on the Indian economy, with special focus on the auto sector, using PE, GE and PE-GE models. The PE model does not predict the change in overall size and price level for the industry well, while the GE model underestimates the aggregate welfare gain due to tariff averaging. It also fails to account for the change in industry composition resulting from trade reform. These findings are robust to wide variation in model parameters. We conclude that the linked model is superior to both the GE and PE counterparts.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-02-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129841828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The economics literature increasingly recognizes the importance of migration and its ties with many other aspects of development and policy. Examples include the role of international remittances (Harrison et al, 2003) or those immigrant-links underpinning the migration-trade nexus (Gould, 1994). More recently Walmsley and Winters (2005) utilised a Global Migration model (GMig) to demonstrate that lifting restrictions on the movement of natural persons would significantly increase global welfare with the majority of benefits accruing to developing countries. Although an important result, the lack of bilateral labor migration data forced Walmsley and Winters (2005) to make approximations in important areas and naturally precluded their tracking bilateral migration agreements. In a new technical paper, Walmsley, Winters, and Ahmed incorporate bilateral labor flows into the GMig model developed by Walmsley and Winters (2005) to examine the impact of liberalizing the temporary movement of natural persons. Quotas on both skilled and unskilled temporary labor in the developed economies are increased by 3% of their labor forces. This additional labor is supplied by the developing economies. The results confirm that restrictions on the movement of natural persons impose significant costs on nearly all countries, and that those on unskilled labor are more burdensome than those on skilled labor. Developed economies increasing their skilled and unskilled labor forces by 3% raise the real incomes of their permanent residents. Most of those gains arise from the lifting of quotas on unskilled labor. On average the permanent residents of developing countries also gain in terms of real incomes from sending unskilled and skilled labor, albeit the gains are lower for skilled labor. While results differ across developing economies, most gain as a result of the higher remittances sent home.
经济学文献越来越认识到移民的重要性及其与发展和政策的许多其他方面的联系。例子包括国际汇款的作用(Harrison et al ., 2003)或支撑移民-贸易关系的移民联系(Gould, 1994)。最近,沃姆斯利和温特斯(2005)利用全球移民模型(GMig)证明,解除对自然人流动的限制将显著增加全球福利,而发展中国家将获得大部分利益。尽管这是一个重要的结果,但缺乏双边劳动力迁移数据迫使沃姆斯利和温特斯(2005)在重要领域做出近似,这自然妨碍了他们追踪双边迁移协议。在一篇新的技术论文中,沃姆斯利、温特斯和艾哈迈德将双边劳动力流动纳入沃姆斯利和温特斯(2005)开发的GMig模型,以检验放宽自然人临时流动的影响。发达经济体对熟练和非熟练临时工的配额增加了其劳动力的3%。这些额外的劳动力由发展中经济体提供。研究结果证实,对自然人流动的限制给几乎所有国家带来了巨大的成本,而且对非熟练劳动力的限制比对熟练劳动力的限制更沉重。发达经济体将熟练和非熟练劳动力增加3%,使其永久居民的实际收入提高3%。这些收益大部分来自于取消对非熟练劳动力的配额。平均而言,发展中国家的永久居民也从输出非熟练和熟练劳动力中获得实际收入,尽管熟练劳动力的收益较低。虽然发展中经济体的结果有所不同,但大多数人都是由于向国内汇款的增加而受益的。
{"title":"Measuring the Impact of the Movement of Labor Using a Model of Bilateral Migration Flows","authors":"T. Walmsley, Alan Winters, S. A. Ahmed","doi":"10.21642/gtap.tp28","DOIUrl":"https://doi.org/10.21642/gtap.tp28","url":null,"abstract":"The economics literature increasingly recognizes the importance of migration and its ties with many other aspects of development and policy. Examples include the role of international remittances (Harrison et al, 2003) or those immigrant-links underpinning the migration-trade nexus (Gould, 1994). More recently Walmsley and Winters (2005) utilised a Global Migration model (GMig) to demonstrate that lifting restrictions on the movement of natural persons would significantly increase global welfare with the majority of benefits accruing to developing countries. Although an important result, the lack of bilateral labor migration data forced Walmsley and Winters (2005) to make approximations in important areas and naturally precluded their tracking bilateral migration agreements. In a new technical paper, Walmsley, Winters, and Ahmed incorporate bilateral labor flows into the GMig model developed by Walmsley and Winters (2005) to examine the impact of liberalizing the temporary movement of natural persons. Quotas on both skilled and unskilled temporary labor in the developed economies are increased by 3% of their labor forces. This additional labor is supplied by the developing economies. The results confirm that restrictions on the movement of natural persons impose significant costs on nearly all countries, and that those on unskilled labor are more burdensome than those on skilled labor. Developed economies increasing their skilled and unskilled labor forces by 3% raise the real incomes of their permanent residents. Most of those gains arise from the lifting of quotas on unskilled labor. On average the permanent residents of developing countries also gain in terms of real incomes from sending unskilled and skilled labor, albeit the gains are lower for skilled labor. While results differ across developing economies, most gain as a result of the higher remittances sent home.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"365 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122342374","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper develops a mathematical programming model to simultaneously estimate re-export markups and reconcile bilateral trade statistics between China, Hong Kong, and their trading partners. The model is applied to sector level trade flows to resolve discrepant reporting in an efficient manner. Adjustments in trade flows are based upon statistical reporters’ reliability information. The program is implemented in GAMS and retains many desirable theoretical and empirical properties. Estimates are used for generating trade flows and markups for Hong Kong’s re-exports used in the forthcoming version 7 GTAP database. The model’s flexibility has potential for expanded use in other regions where re-exports and associated markup cause discrepant trade flows.
{"title":"Reconciling Trade Statistics from China, Hong Kong and Their Major Trading Partners--A Mathematical Programming Approach","authors":"Zhi Wang, M. Gehlhar, S. Yao","doi":"10.21642/gtap.tp27","DOIUrl":"https://doi.org/10.21642/gtap.tp27","url":null,"abstract":"This paper develops a mathematical programming model to simultaneously estimate re-export markups and reconcile bilateral trade statistics between China, Hong Kong, and their trading partners. The model is applied to sector level trade flows to resolve discrepant reporting in an efficient manner. Adjustments in trade flows are based upon statistical reporters’ reliability information. The program is implemented in GAMS and retains many desirable theoretical and empirical properties. Estimates are used for generating trade flows and markups for Hong Kong’s re-exports used in the forthcoming version 7 GTAP database. The model’s flexibility has potential for expanded use in other regions where re-exports and associated markup cause discrepant trade flows.","PeriodicalId":281904,"journal":{"name":"GTAP Technical Paper Series","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-09-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124036743","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}