As the use of payments for environmental services (PES) programs for conservation has grown in developing countries, the use of stated preference methods, particularly contingent valuation (CV) surveys, to estimate the maximum amount that users of environmental services (buyers) would be willing to pay has also increased. This paper reviews 25 CV studies conducted in the context of PES programs (CV-PES) and assesses their quality and usefulness for designing PES programs. Almost all these studies attempt to estimate the demand of downstream water users for up-stream watershed protection and, more generally, for improved water services. Most studies were methodologically uninspired and generally low-quality applications of stated preference methods, with limited policy relevance. The quality and usefulness of CV-PES studies could be substantially improved at only a modest increase in costs.
{"title":"Using contingent valuation in the design of payments for environmental services mechanisms: a review and assessment","authors":"D. Whittington, S. Pagiola","doi":"10.1093/WBRO/LKS004","DOIUrl":"https://doi.org/10.1093/WBRO/LKS004","url":null,"abstract":"As the use of payments for environmental services (PES) programs for conservation has grown in developing countries, the use of stated preference methods, particularly contingent valuation (CV) surveys, to estimate the maximum amount that users of environmental services (buyers) would be willing to pay has also increased. This paper reviews 25 CV studies conducted in the context of PES programs (CV-PES) and assesses their quality and usefulness for designing PES programs. Almost all these studies attempt to estimate the demand of downstream water users for up-stream watershed protection and, more generally, for improved water services. Most studies were methodologically uninspired and generally low-quality applications of stated preference methods, with limited policy relevance. The quality and usefulness of CV-PES studies could be substantially improved at only a modest increase in costs.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"81 1","pages":"261-287"},"PeriodicalIF":8.1,"publicationDate":"2012-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85942499","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A large body of literature has arisen in economics and political science analyzing the apparent "resource curse"--the tendency of countries with high levels of natural resources to exhibit worse economic and political outcomes. The author examines the purported causal mechanisms underlying this "curse" and shows that they all center on the revenue that these resources generate for the government. As such, it is not surprising that the most recent literature on the topic has demonstrated that, in the hands of a competent government, natural resources have no negative consequences and may actually have positive effects. The important question therefore is: What can be done in countries without effective governments? Policy proposals have centered on (a) taking the resources out of the hands of the government or (b) having the government commit to use the funds in certain ways. Neither of these has been particularly successful, which we might have predicted from research on another important nontax revenue source for developing countries: foreign aid. The close parallels between the foreign aid and "resource curse" literatures are reviewed, as are the lessons from the aid literature. These lessons suggest the need for an important change in approach toward poorly governed resource-rich countries. Copyright 2012, Oxford University Press.
{"title":"What Can We Learn about the “Resource Curse” from Foreign Aid?","authors":"Kevin Morrison","doi":"10.1093/WBRO/LKQ013","DOIUrl":"https://doi.org/10.1093/WBRO/LKQ013","url":null,"abstract":"A large body of literature has arisen in economics and political science analyzing the apparent \"resource curse\"--the tendency of countries with high levels of natural resources to exhibit worse economic and political outcomes. The author examines the purported causal mechanisms underlying this \"curse\" and shows that they all center on the revenue that these resources generate for the government. As such, it is not surprising that the most recent literature on the topic has demonstrated that, in the hands of a competent government, natural resources have no negative consequences and may actually have positive effects. The important question therefore is: What can be done in countries without effective governments? Policy proposals have centered on (a) taking the resources out of the hands of the government or (b) having the government commit to use the funds in certain ways. Neither of these has been particularly successful, which we might have predicted from research on another important nontax revenue source for developing countries: foreign aid. The close parallels between the foreign aid and \"resource curse\" literatures are reviewed, as are the lessons from the aid literature. These lessons suggest the need for an important change in approach toward poorly governed resource-rich countries. Copyright 2012, Oxford University Press.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"97 1","pages":"52-73"},"PeriodicalIF":8.1,"publicationDate":"2012-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74822389","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The author reviews trends in rural electrification over the past 30 years in Sub-Saharan Africa. In particular, it is shown that motivations for rural electrification programs have evolved significantly over the years, following changes in development paradigms. The author finds, that knowledge of the impact of this has only marginally improved: low connection rates and weak productive utilization identified in the 1980s remain true today, and impacts on such dimensions as health, education, or income, though often used to justify projects, are largely undocumented. Indeed impact evaluations are methodologically challenging in the field of infrastructures and have been limited thus far. Nevertheless examples of recent or ongoing impact evaluations of rural electrification programs offer promising avenues for identifying both the effect of electricity per se and the relative effectiveness of approaches to promoting it.
{"title":"Impact Analysis of Rural Electrification Projects in Sub-Saharan Africa","authors":"Tanguy Bernard","doi":"10.1093/WBRO/LKQ008","DOIUrl":"https://doi.org/10.1093/WBRO/LKQ008","url":null,"abstract":"The author reviews trends in rural electrification over the past 30 years in Sub-Saharan Africa. In particular, it is shown that motivations for rural electrification programs have evolved significantly over the years, following changes in development paradigms. The author finds, that knowledge of the impact of this has only marginally improved: low connection rates and weak productive utilization identified in the 1980s remain true today, and impacts on such dimensions as health, education, or income, though often used to justify projects, are largely undocumented. Indeed impact evaluations are methodologically challenging in the field of infrastructures and have been limited thus far. Nevertheless examples of recent or ongoing impact evaluations of rural electrification programs offer promising avenues for identifying both the effect of electricity per se and the relative effectiveness of approaches to promoting it.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"30 1","pages":"33-51"},"PeriodicalIF":8.1,"publicationDate":"2012-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"87897359","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ever since development economics became a field, there has been a search for “the” key to development. Physical capital accumulation, human capital, industrial development, institutional quality, social capital, and a variety of other factors have been the focus at one time or another. As each became the focal point, there was a parallel explicit or implied role of government. If I understand Justin Lin correctly, he is saying that the “new structural economics” (NSE) accepts that earlier thought ignored comparative advantage, which should be market determined, but that growth requires improvements in ‘hard’ (tangible) and ‘soft’ (intangible) infrastructure at each stage. Such upgrading and improvements require coordination and inhere with large externalities to firms' transaction costs and returns to capital investment. Thus, in addition to an effective market mechanism, the government should play an active role in facilitating structural change (p. 206). He seems also to believe that growth depends almo...
{"title":"Comments on “New Structural Economics” by Justin Yifu Lin","authors":"A. Krueger","doi":"10.1093/WBRO/LKR010","DOIUrl":"https://doi.org/10.1093/WBRO/LKR010","url":null,"abstract":"Ever since development economics became a field, there has been a search for “the” key to development. Physical capital accumulation, human capital, industrial development, institutional quality, social capital, and a variety of other factors have been the focus at one time or another. As each became the focal point, there was a parallel explicit or implied role of government. If I understand Justin Lin correctly, he is saying that the “new structural economics” (NSE) accepts that earlier thought ignored comparative advantage, which should be market determined, but that growth requires improvements in ‘hard’ (tangible) and ‘soft’ (intangible) infrastructure at each stage. Such upgrading and improvements require coordination and inhere with large externalities to firms' transaction costs and returns to capital investment. Thus, in addition to an effective market mechanism, the government should play an active role in facilitating structural change (p. 206). He seems also to believe that growth depends almo...","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"95 1","pages":"222-226"},"PeriodicalIF":8.1,"publicationDate":"2011-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75932722","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Justin Lin wants to make structuralist economics respectable again, and I applaud him for that. He wants to marry structuralism with neoclassical economic reasoning, and I applaud this idea too. So he has two cheers from me. I withhold my third cheer so I can quibble with some of what he writes. The central insight of structuralism is that developing countries are qualitatively different from developed ones. They are not just radially shrunk versions of rich countries. In order to understand the challenges of under-development, you have to understand how the structure of employment and production—in particular the large gaps between the social marginal products of labor in traditional versus modern activities—is determined and how the obstacles that block structural transformation can be overcome. The central insight of neoclassical economics is that people respond to incentives. We need to understand the incentives of, say, teachers to show up for work and impart valuable skills to their students or of e...
{"title":"Comments on “New Structural Economics” by Justin Yifu Lin","authors":"D. Rodrik","doi":"10.1093/WBRO/LKR008","DOIUrl":"https://doi.org/10.1093/WBRO/LKR008","url":null,"abstract":"Justin Lin wants to make structuralist economics respectable again, and I applaud him for that. He wants to marry structuralism with neoclassical economic reasoning, and I applaud this idea too. So he has two cheers from me. I withhold my third cheer so I can quibble with some of what he writes. The central insight of structuralism is that developing countries are qualitatively different from developed ones. They are not just radially shrunk versions of rich countries. In order to understand the challenges of under-development, you have to understand how the structure of employment and production—in particular the large gaps between the social marginal products of labor in traditional versus modern activities—is determined and how the obstacles that block structural transformation can be overcome. The central insight of neoclassical economics is that people respond to incentives. We need to understand the incentives of, say, teachers to show up for work and impart valuable skills to their students or of e...","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"28 1","pages":"227-229"},"PeriodicalIF":8.1,"publicationDate":"2011-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90985844","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The authors summarize the extant literature on the relationship between gender and entrepreneurship. They note significant quantitative gender differences in business entry, with male-owned firms heavily prevailing over firms owned by women in many parts of the world. They find that enterprises owned by men on the one hand and women on the other are generally concentrated in different sectors, women entrepreneurs being better represented in labor intensive sectors such as trade and services rather than capital intensive manufacturing industries. They also observe certain gender differentials in business survival and growth patterns. Yet an analysis of a large body of literature does not suggest that, in general, the so called "gender gap" in entrepreneurship can be explained by explicit discrimination in laws or regulations. Rather, differences in quantitative and qualitative indicators of business entry and performance can in part be explained by a number of business environment factors that disproportionately affect a woman's decision to operate a business in the formal sector. For example the concentration of women in low capital intensive industries--which require less funding and at the same time have a lower potential for growth and development--might also be driven by barriers against women regarding access to finance. Furthermore, women may have relatively less physical and "reputational" collateral than men, which limits their access to finance. Overall the literature suggests that improvements in the business environment can help promote high-growth female entrepreneurship. Copyright 2011, Oxford University Press.
{"title":"Gender and the business environment for new firm creation","authors":"Leora F. Klapper, S. Parker","doi":"10.1093/WBRO/LKP032","DOIUrl":"https://doi.org/10.1093/WBRO/LKP032","url":null,"abstract":"The authors summarize the extant literature on the relationship between gender and entrepreneurship. They note significant quantitative gender differences in business entry, with male-owned firms heavily prevailing over firms owned by women in many parts of the world. They find that enterprises owned by men on the one hand and women on the other are generally concentrated in different sectors, women entrepreneurs being better represented in labor intensive sectors such as trade and services rather than capital intensive manufacturing industries. They also observe certain gender differentials in business survival and growth patterns. Yet an analysis of a large body of literature does not suggest that, in general, the so called \"gender gap\" in entrepreneurship can be explained by explicit discrimination in laws or regulations. Rather, differences in quantitative and qualitative indicators of business entry and performance can in part be explained by a number of business environment factors that disproportionately affect a woman's decision to operate a business in the formal sector. For example the concentration of women in low capital intensive industries--which require less funding and at the same time have a lower potential for growth and development--might also be driven by barriers against women regarding access to finance. Furthermore, women may have relatively less physical and \"reputational\" collateral than men, which limits their access to finance. Overall the literature suggests that improvements in the business environment can help promote high-growth female entrepreneurship. Copyright 2011, Oxford University Press.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"78 1","pages":"237-257"},"PeriodicalIF":8.1,"publicationDate":"2011-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90292141","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Twelve years ago, when I was chief economist of the World Bank, I suggested that the major challenge to development economics was learning the lessons of the previous several decades: a small group of countries, mostly in Asia, but a few in other regions, had had phenomenal success, beyond anything that had been anticipated by economists; while many other countries had experienced slow growth, or even worse, stagnation and decline—inconsistent with the standard models in economics which predicted convergence. The successful countries had followed policies that were markedly different from those of the Washington Consensus, though they shared some elements in common; those policies had not brought high growth, stability, or poverty reduction. Shortly after I left the World Bank, the crisis in Argentina—which had been held up as the poster child of the country that had followed Washington Consensus policies—reinforced the doubts about that strategy. The global financial crisis, too, has cast doubt over the neoclassical paradigm in advanced industrial countries, and rightly so. Much of development economics had been viewed as asking how developing countries could successfully transition toward the kinds of market-oriented policy frameworks that came to be called “American style capitalism.” The debate was not about the goal, but the path to that goal, with some advocating “shock therapy,” while others focused on pacing and sequencing—a more gradualist tack. The global financial crisis has now raised questions about that model even for developed countries. In this short essay, I want to argue that the long-term experiences in growth and stability of both developed and less developed countries, as well as the deeper theoretical understanding of the strengths and limitations of market economies, provide support for a “new structural” approach to development—an approach
{"title":"Rethinking Development Economics","authors":"J. Stiglitz","doi":"10.1093/WBRO/LKR011","DOIUrl":"https://doi.org/10.1093/WBRO/LKR011","url":null,"abstract":"Twelve years ago, when I was chief economist of the World Bank, I suggested that the major challenge to development economics was learning the lessons of the previous several decades: a small group of countries, mostly in Asia, but a few in other regions, had had phenomenal success, beyond anything that had been anticipated by economists; while many other countries had experienced slow growth, or even worse, stagnation and decline—inconsistent with the standard models in economics which predicted convergence. The successful countries had followed policies that were markedly different from those of the Washington Consensus, though they shared some elements in common; those policies had not brought high growth, stability, or poverty reduction. Shortly after I left the World Bank, the crisis in Argentina—which had been held up as the poster child of the country that had followed Washington Consensus policies—reinforced the doubts about that strategy. The global financial crisis, too, has cast doubt over the neoclassical paradigm in advanced industrial countries, and rightly so. Much of development economics had been viewed as asking how developing countries could successfully transition toward the kinds of market-oriented policy frameworks that came to be called “American style capitalism.” The debate was not about the goal, but the path to that goal, with some advocating “shock therapy,” while others focused on pacing and sequencing—a more gradualist tack. The global financial crisis has now raised questions about that model even for developed countries. In this short essay, I want to argue that the long-term experiences in growth and stability of both developed and less developed countries, as well as the deeper theoretical understanding of the strengths and limitations of market economies, provide support for a “new structural” approach to development—an approach","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"16 1","pages":"230-236"},"PeriodicalIF":8.1,"publicationDate":"2011-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89633085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This report surveys a vast body of literature devoted to evaluating the relationship between corporate governance and performance as measured by valuation, operating performance or stock returns. Most of the evidence to date suggests a positive association between corporate governance and various measures of performance. However, this line of research suffers from endogeneity problems that are difficult to resolve. There is no consensus yet on the nature of the endogeneity in governance-performance studies and this survey proposes an approach to resolve it. The emerging conclusion is that corporate governance is likely to develop endogenously and depend on specific characteristics of the firm and its environment.
{"title":"Corporate governance and performance around the world : What we know and what we don't","authors":"Inessa Love","doi":"10.1093/WBRO/LKP030","DOIUrl":"https://doi.org/10.1093/WBRO/LKP030","url":null,"abstract":"This report surveys a vast body of literature devoted to evaluating the relationship between corporate governance and performance as measured by valuation, operating performance or stock returns. Most of the evidence to date suggests a positive association between corporate governance and various measures of performance. However, this line of research suffers from endogeneity problems that are difficult to resolve. There is no consensus yet on the nature of the endogeneity in governance-performance studies and this survey proposes an approach to resolve it. The emerging conclusion is that corporate governance is likely to develop endogenously and depend on specific characteristics of the firm and its environment.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"139 1","pages":"42-70"},"PeriodicalIF":8.1,"publicationDate":"2011-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85325060","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Urban transportation externalities are a key development challenge. Based on the existing literature, the authors illustrate the magnitudes of various external costs, re view response policies, and measure and discuss their selection, particularly focusing on the context of developing countries. They find that regulatory policy instruments aimed at reducing local air pollution have been introduced in most countries in the world. On the other hand, fiscal policy instruments aimed at reducing congestion or greenhouse gas emissions are limited mainly to industrialized economies. Although traditional fiscal instruments, such as fuel taxes and subsidies, are normally introduced for other purposes, they can also help to reduce externalities. Land use or urban planning, and infrastructure investment, could also contribute to reducing externalities; but they are expensive and play a small role in already developed megacities. The main factors that influence the choice of policy instruments include economic efficiency, equity, country or city specific priority, and institutional capacity for implementation. Multiple policy options need to be used simultaneously to reduce effectively the different externalities arising from urban road transportation because most policy options are not mutually exclusive.
{"title":"Urban Road Transportation Externalities: Costs and Choice of Policy Instruments","authors":"G. Timilsina, H. Dulal","doi":"10.1093/WBRO/LKQ005","DOIUrl":"https://doi.org/10.1093/WBRO/LKQ005","url":null,"abstract":"Urban transportation externalities are a key development challenge. Based on the existing literature, the authors illustrate the magnitudes of various external costs, re view response policies, and measure and discuss their selection, particularly focusing on the context of developing countries. They find that regulatory policy instruments aimed at reducing local air pollution have been introduced in most countries in the world. On the other hand, fiscal policy instruments aimed at reducing congestion or greenhouse gas emissions are limited mainly to industrialized economies. Although traditional fiscal instruments, such as fuel taxes and subsidies, are normally introduced for other purposes, they can also help to reduce externalities. Land use or urban planning, and infrastructure investment, could also contribute to reducing externalities; but they are expensive and play a small role in already developed megacities. The main factors that influence the choice of policy instruments include economic efficiency, equity, country or city specific priority, and institutional capacity for implementation. Multiple policy options need to be used simultaneously to reduce effectively the different externalities arising from urban road transportation because most policy options are not mutually exclusive.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"18 1","pages":"162-191"},"PeriodicalIF":8.1,"publicationDate":"2011-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76374981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Testing is a potentially important intervention to slow the Human Immunodeficiency Virus (HIV) epidemic in Africa and elsewhere. Some countries in Africa have achieved high levels of testing but most have not. Cost, price, and questions of confidentiality have limited the expansion of testing. It looks possible, however, that there are choices as to the design of testing programs that would expand the number of people who could know their HIV status in ways that would be worthwhile.
{"title":"HIV Testing: Principles and Practice","authors":"M. Gersovitz","doi":"10.1093/WBRO/LKP013","DOIUrl":"https://doi.org/10.1093/WBRO/LKP013","url":null,"abstract":"Testing is a potentially important intervention to slow the Human Immunodeficiency Virus (HIV) epidemic in Africa and elsewhere. Some countries in Africa have achieved high levels of testing but most have not. Cost, price, and questions of confidentiality have limited the expansion of testing. It looks possible, however, that there are choices as to the design of testing programs that would expand the number of people who could know their HIV status in ways that would be worthwhile.","PeriodicalId":47647,"journal":{"name":"World Bank Research Observer","volume":"65 1","pages":"1-41"},"PeriodicalIF":8.1,"publicationDate":"2011-02-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79615145","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"经济学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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