Pub Date : 2021-01-01DOI: 10.2478/izajodm-2021-0012
C. Krafft, R. Assaad, K. Rahman
Abstract This paper introduces the 2018 wave of the Egypt Labor Market Panel Survey (ELMPS), previously fielded in 1998, 2006, and 2012. The ELMPS has already become the primary source of data for a large number of scholarly and policy studies on the labor market and human development issues in Egypt, and this new wave will further enhance its value as a critical data public good. This longitudinal survey is nationally representative, tracking both households and individuals over two decades. In this paper, we describe the key characteristics of the 2018 wave, including sampling, fielding, and questionnaire design. Changes in the collection of retrospective data starting in 2018 are discussed, and we demonstrate that they improved the data quality. We examine the patterns of attrition and present the construction of weights designed to correct for attrition, as well as to ensure that the sample remains nationally representative. We compare the ELMPS data with other Egyptian data sources, namely, the 2017 Census and various rounds of the Labor Force Survey (LFS). The data provide important new insights into Egypt's labor market, economy, and society.
{"title":"Introducing the Egypt Labor Market Panel Survey 2018","authors":"C. Krafft, R. Assaad, K. Rahman","doi":"10.2478/izajodm-2021-0012","DOIUrl":"https://doi.org/10.2478/izajodm-2021-0012","url":null,"abstract":"Abstract This paper introduces the 2018 wave of the Egypt Labor Market Panel Survey (ELMPS), previously fielded in 1998, 2006, and 2012. The ELMPS has already become the primary source of data for a large number of scholarly and policy studies on the labor market and human development issues in Egypt, and this new wave will further enhance its value as a critical data public good. This longitudinal survey is nationally representative, tracking both households and individuals over two decades. In this paper, we describe the key characteristics of the 2018 wave, including sampling, fielding, and questionnaire design. Changes in the collection of retrospective data starting in 2018 are discussed, and we demonstrate that they improved the data quality. We examine the patterns of attrition and present the construction of weights designed to correct for attrition, as well as to ensure that the sample remains nationally representative. We compare the ELMPS data with other Egyptian data sources, namely, the 2017 Census and various rounds of the Labor Force Survey (LFS). The data provide important new insights into Egypt's labor market, economy, and society.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49282467","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}
Pub Date : 2021-01-01DOI: 10.2478/izajodm-2021-0011
Brianna O’Steen
Abstract Bilateral labor agreements (BLAs) are preferred policy models for regulating migration by many governments around the world. The Philippines has been a leader in both agreement conclusion and exporting labor. A recent Congressional evocation is pushing bureaucrats and academics alike to investigate this policy strategy for outcomes and effectiveness. The following analysis answers the question “Do BLAs affect the migration outflows of Overseas Filipino Workers (OFWs)?” using a plausibly exogenous variation to isolate a causal effect. I test for effects of BLAs using two instrumental variables (IVs), such as Bilateral Investment Treaties (BITs) and Formal Alliances, and an original dataset of land-based and sea-based Filipino BLAs and migrant stock in 213 unique areas from 1960 to 2018. I do not find any empirical evidence that these treaties drive migration. However, BLAs have statistically significant effects on gross domestic product (GDP) per capita and exports, suggesting other important channels through which these agreements affect economic outcomes. These null results are critically important for policymakers and diplomats because the resources spent on negotiation are wasted if the primary goal is to increase migration.
{"title":"Bilateral labor agreements and the migration of Filipinos: An instrumental variable approach","authors":"Brianna O’Steen","doi":"10.2478/izajodm-2021-0011","DOIUrl":"https://doi.org/10.2478/izajodm-2021-0011","url":null,"abstract":"Abstract Bilateral labor agreements (BLAs) are preferred policy models for regulating migration by many governments around the world. The Philippines has been a leader in both agreement conclusion and exporting labor. A recent Congressional evocation is pushing bureaucrats and academics alike to investigate this policy strategy for outcomes and effectiveness. The following analysis answers the question “Do BLAs affect the migration outflows of Overseas Filipino Workers (OFWs)?” using a plausibly exogenous variation to isolate a causal effect. I test for effects of BLAs using two instrumental variables (IVs), such as Bilateral Investment Treaties (BITs) and Formal Alliances, and an original dataset of land-based and sea-based Filipino BLAs and migrant stock in 213 unique areas from 1960 to 2018. I do not find any empirical evidence that these treaties drive migration. However, BLAs have statistically significant effects on gross domestic product (GDP) per capita and exports, suggesting other important channels through which these agreements affect economic outcomes. These null results are critically important for policymakers and diplomats because the resources spent on negotiation are wasted if the primary goal is to increase migration.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41424428","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}
Pub Date : 2021-01-01DOI: 10.2478/izajodm-2021-0014
Ezgi Kaya
Abstract This paper studies the role of within- and between-firm effects on the gender wage gap (GWG). Using linked employer–employee data for Turkey for 2006 and 2014, we show that the wage gap among comparable men and women is much wider within establishments than between establishments. Our distributional analysis shows a more pronounced gap among highly paid workers, consistent with the presence of a glass-ceiling effect. This effect, however, is more apparent within establishments than between establishments, and it is the former that drives the economy-wide glass ceiling that women face. We also find that between 2006 and 2014, the GWG in Turkey widened at all points in the wage distribution, and that this widening was more pronounced within establishments than between establishments.
{"title":"Gender wage gap across the distribution: What is the role of within- and between-firm effects?","authors":"Ezgi Kaya","doi":"10.2478/izajodm-2021-0014","DOIUrl":"https://doi.org/10.2478/izajodm-2021-0014","url":null,"abstract":"Abstract This paper studies the role of within- and between-firm effects on the gender wage gap (GWG). Using linked employer–employee data for Turkey for 2006 and 2014, we show that the wage gap among comparable men and women is much wider within establishments than between establishments. Our distributional analysis shows a more pronounced gap among highly paid workers, consistent with the presence of a glass-ceiling effect. This effect, however, is more apparent within establishments than between establishments, and it is the former that drives the economy-wide glass ceiling that women face. We also find that between 2006 and 2014, the GWG in Turkey widened at all points in the wage distribution, and that this widening was more pronounced within establishments than between establishments.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47728229","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}
Pub Date : 2021-01-01DOI: 10.2478/izajodm-2021-0013
E. Neumayer, Thomas Plümper
Abstract There is a large variation across countries of origin in the gender composition of migrants coming to Germany. We argue that women’s economic rights in developing countries of origin have three effects on their migration prospects to a place like Germany that is far away and difficult to reach. First, the lower are women’s economic rights the fewer women have access to and control over the resources needed to migrate to Germany. Second, the lower are the rights the lower is women’s agency to make or otherwise influence migration decisions. These two constraining effects on the female share in migrant populations dominate the opposing third effect that stems from low levels of women’s economic rights generating a potentially powerful push factor. We find corroborating evidence in our analysis of the gender composition of migration to Germany over the period 2009–2017.
{"title":"Women’s economic rights in developing countries and the gender gap in migration to Germany","authors":"E. Neumayer, Thomas Plümper","doi":"10.2478/izajodm-2021-0013","DOIUrl":"https://doi.org/10.2478/izajodm-2021-0013","url":null,"abstract":"Abstract There is a large variation across countries of origin in the gender composition of migrants coming to Germany. We argue that women’s economic rights in developing countries of origin have three effects on their migration prospects to a place like Germany that is far away and difficult to reach. First, the lower are women’s economic rights the fewer women have access to and control over the resources needed to migrate to Germany. Second, the lower are the rights the lower is women’s agency to make or otherwise influence migration decisions. These two constraining effects on the female share in migrant populations dominate the opposing third effect that stems from low levels of women’s economic rights generating a potentially powerful push factor. We find corroborating evidence in our analysis of the gender composition of migration to Germany over the period 2009–2017.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45737069","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}
Abstract Despite informality being the norm in conflict-affected countries, most estimates of the impact of conflict on economic activity rely on formal sector data. Using high-frequency data from Afghanistan, this paper assesses how surges in conflict intensity affect not only the formal sector, but also informal and illicit activities. Nighttime light provides a proxy for aggregate economic activity, mobile phone traffic by registered firms captures fluctuations in formal sector output, and the land surface devoted to poppy cultivation gives a measure of illicit production. The unit of observation is the district and the period of reference is 2012–2016. The results show that an increase in conflict-related casualties has a strong negative impact on formal economic activity in the following quarter and a positive effect on illicit activity after two quarters. The impact on aggregate economic activity is negative, but more muted.
{"title":"Conflict and the composition of economic activity in Afghanistan","authors":"V. Galdo, Gladys Lopez Acevedo, M. Rama","doi":"10.1596/1813-9450-9188","DOIUrl":"https://doi.org/10.1596/1813-9450-9188","url":null,"abstract":"Abstract Despite informality being the norm in conflict-affected countries, most estimates of the impact of conflict on economic activity rely on formal sector data. Using high-frequency data from Afghanistan, this paper assesses how surges in conflict intensity affect not only the formal sector, but also informal and illicit activities. Nighttime light provides a proxy for aggregate economic activity, mobile phone traffic by registered firms captures fluctuations in formal sector output, and the land surface devoted to poppy cultivation gives a measure of illicit production. The unit of observation is the district and the period of reference is 2012–2016. The results show that an increase in conflict-related casualties has a strong negative impact on formal economic activity in the following quarter and a positive effect on illicit activity after two quarters. The impact on aggregate economic activity is negative, but more muted.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41306559","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}
Pub Date : 2020-01-01DOI: 10.2478/izajodm-2020-0015
B. Bedasso, Pascal Jaupart
Abstract Little is known about the political consequences of immigration in Sub-Saharan Africa. In this paper, we estimate the effect of exposure to immigration on election outcomes in South Africa. Our analysis is based on municipality panel data and an instrumental variable (IV) strategy exploiting historical migrant settlement patterns. We find that local immigration concentration has a negative impact on the performance of the incumbent African National Congress, whereas support for the main opposition party, the Democratic Alliance, is found to increase in municipalities with a larger immigrant presence. These effects hold regardless of the skill levels of immigrants in a municipality. In terms of mechanisms, competition over jobs and local public services as well as ethnic diversity and cultural factors influence how immigration affects election outcomes. These findings are robust to a broad range of sensitivity checks. They provide evidence that immigration can be a politically salient issue in migrant-destination Sub-Saharan African countries. They also show that immigration can affect election results even in contexts where there is no single issue anti-migrant party.
{"title":"South-South migration and elections: evidence from post-apartheid South Africa","authors":"B. Bedasso, Pascal Jaupart","doi":"10.2478/izajodm-2020-0015","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0015","url":null,"abstract":"Abstract Little is known about the political consequences of immigration in Sub-Saharan Africa. In this paper, we estimate the effect of exposure to immigration on election outcomes in South Africa. Our analysis is based on municipality panel data and an instrumental variable (IV) strategy exploiting historical migrant settlement patterns. We find that local immigration concentration has a negative impact on the performance of the incumbent African National Congress, whereas support for the main opposition party, the Democratic Alliance, is found to increase in municipalities with a larger immigrant presence. These effects hold regardless of the skill levels of immigrants in a municipality. In terms of mechanisms, competition over jobs and local public services as well as ethnic diversity and cultural factors influence how immigration affects election outcomes. These findings are robust to a broad range of sensitivity checks. They provide evidence that immigration can be a politically salient issue in migrant-destination Sub-Saharan African countries. They also show that immigration can affect election results even in contexts where there is no single issue anti-migrant party.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44929146","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}
Pub Date : 2020-01-01DOI: 10.2478/izajodm-2020-0009
Eric M. Gibbons, S. Mukhopadhyay
Abstract This article sheds new light on the portability of human capital. We estimate the returns to source country experiences, viz., general, occupation-specific, and task-specific experiences, using data from the New Immigrant Survey (NIS), conducted in 2003. While the “returns to general experience” has been discussed in the literature, we are not aware of any previous attempt to estimate the returns to source country occupation-specific and task-specific experiences. Our estimates show that even though the returns to source country general experience is negligible, returns to source country occupation-specific experience is economically and statistically significant. We also find that returns to source country abstract (specifically analytical) task-specific experience is substantial and significant. Our results are robust to inclusion of source country wage, which may reflect unobservable characteristics that influence wages. We explore whether returns to work experience vary by income level in the source country or by an immigrant’s skill level.
{"title":"New Evidence on International Transferability of Human Capital","authors":"Eric M. Gibbons, S. Mukhopadhyay","doi":"10.2478/izajodm-2020-0009","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0009","url":null,"abstract":"Abstract This article sheds new light on the portability of human capital. We estimate the returns to source country experiences, viz., general, occupation-specific, and task-specific experiences, using data from the New Immigrant Survey (NIS), conducted in 2003. While the “returns to general experience” has been discussed in the literature, we are not aware of any previous attempt to estimate the returns to source country occupation-specific and task-specific experiences. Our estimates show that even though the returns to source country general experience is negligible, returns to source country occupation-specific experience is economically and statistically significant. We also find that returns to source country abstract (specifically analytical) task-specific experience is substantial and significant. Our results are robust to inclusion of source country wage, which may reflect unobservable characteristics that influence wages. We explore whether returns to work experience vary by income level in the source country or by an immigrant’s skill level.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42648102","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}
Pub Date : 2020-01-01DOI: 10.2478/izajodm-2020-0004
Ilhom Abdulloev, G. Epstein, Ira N. Gang
Abstract Large international earnings differentials negatively impact human capital investments in migrant-origin countries. We find that three Central Asian migrant-sending countries—the Kyrgyz Republic, the Republic of Tajikistan, and the Republic of Uzbekistan—are facing a forsaken schooling phenomenon. Once completing their compulsory schooling, young people in these countries are forsaking additional schooling because of opportunities to migrate to high-paying low-skilled jobs in the Russian Federation. The countries face a loss in human capital formation.
{"title":"Migration and Forsaken Schooling in Kyrgyzstan, Tajikistan, and Uzbekistan","authors":"Ilhom Abdulloev, G. Epstein, Ira N. Gang","doi":"10.2478/izajodm-2020-0004","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0004","url":null,"abstract":"Abstract Large international earnings differentials negatively impact human capital investments in migrant-origin countries. We find that three Central Asian migrant-sending countries—the Kyrgyz Republic, the Republic of Tajikistan, and the Republic of Uzbekistan—are facing a forsaken schooling phenomenon. Once completing their compulsory schooling, young people in these countries are forsaking additional schooling because of opportunities to migrate to high-paying low-skilled jobs in the Russian Federation. The countries face a loss in human capital formation.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47778476","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}
Pub Date : 2020-01-01DOI: 10.2478/IZAJODM-2020-0022
Shan Li
This article studies the role of rainfall in determining the education composition of Mexico-US migration. Emphasizing the relationship between rainfall and migration costs, a revised Roy model indicates that rainfall affects selection on education through not only households’ liquidity constraints but also the comparisons between changes in migration costs and wage differentials at different levels of education. With retrospective data on the migration history of male Mexicans, the empirical analysis shows that the inverted U-shaped relationship between migration probabilities and education is less dispersed with a higher vertex when rainfall decreases, suggesting higher migration costs and reinforced self-selection patterns. The impacts of rainfall on selection and education are stronger for the migrant stock than for migration flows. Studying how rainfall influences migrants’ return decisions provides consistent results.
{"title":"Rainfall and self-selection patterns in Mexico-US migration","authors":"Shan Li","doi":"10.2478/IZAJODM-2020-0022","DOIUrl":"https://doi.org/10.2478/IZAJODM-2020-0022","url":null,"abstract":"\u0000 This article studies the role of rainfall in determining the education composition of Mexico-US migration. Emphasizing the relationship between rainfall and migration costs, a revised Roy model indicates that rainfall affects selection on education through not only households’ liquidity constraints but also the comparisons between changes in migration costs and wage differentials at different levels of education. With retrospective data on the migration history of male Mexicans, the empirical analysis shows that the inverted U-shaped relationship between migration probabilities and education is less dispersed with a higher vertex when rainfall decreases, suggesting higher migration costs and reinforced self-selection patterns. The impacts of rainfall on selection and education are stronger for the migrant stock than for migration flows. Studying how rainfall influences migrants’ return decisions provides consistent results.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44473419","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}
Pub Date : 2020-01-01DOI: 10.2478/izajodm-2020-0007
Daniel Auer, Friederike Römer, Jasper Tjaden
Abstract Whether and to what extent corruption drives emigration has received growing attention in the literature in recent years, yet the nature of the relationship remains unclear. To test causal claims, we rely on representative global survey data of more than 280,000 respondents across 67 countries from 2010 to 2014. We use two different measures of emigration intentions and individual, as well as country-level measures of corruption, and propose to instrument the endogenous presence of corruption in a country with the prevalence of cashless transactions in the economy to correct for potential estimation bias. We find robust support for the hypothesis that corruption increases emigration intentions across countries. The effect, however, is likely to be underestimated in conventional models that do not account for endogeneity. The results highlight the need to look beyond purely economic, social, security-related, and environmental drivers when assessing the root causes of migration.
{"title":"Corruption and the Desire to Leave Quasi-Experimental Evidence on Corruption as a Driver of Emigration Intentions","authors":"Daniel Auer, Friederike Römer, Jasper Tjaden","doi":"10.2478/izajodm-2020-0007","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0007","url":null,"abstract":"Abstract Whether and to what extent corruption drives emigration has received growing attention in the literature in recent years, yet the nature of the relationship remains unclear. To test causal claims, we rely on representative global survey data of more than 280,000 respondents across 67 countries from 2010 to 2014. We use two different measures of emigration intentions and individual, as well as country-level measures of corruption, and propose to instrument the endogenous presence of corruption in a country with the prevalence of cashless transactions in the economy to correct for potential estimation bias. We find robust support for the hypothesis that corruption increases emigration intentions across countries. The effect, however, is likely to be underestimated in conventional models that do not account for endogeneity. The results highlight the need to look beyond purely economic, social, security-related, and environmental drivers when assessing the root causes of migration.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43754120","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}
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