Pub Date : 2020-01-01DOI: 10.2478/izajodm-2020-0003
C. Economidou, D. Karamanis, Alexandra Kechrinioti, S. Xesfingi
Abstract Migration has manifested itself to historic highs, creating divisive views among politicians, policy makers, and individuals. The present paper studies the Europeans’ attitudes toward immigration, focusing particularly on the role of social capital. Based on 267,282 respondents from 22 countries and over the period 2002–2014, we find that despite the eventful past years, Europeans, on average, are positive toward immigrants with the North European countries to be the least xenophobic. A salient finding of our analysis is that regardless of the impact of other contextual factors, namely, a country’s macroeconomic conditions, ethnic diversity, cultural origin, and individuals’ attributes, social capital associates with positive attitudes toward all immigrants, independent of their background. Furthermore, social capital moderates the negative effects of perceived threat on people’s opinions about immigrants.
{"title":"The Role of Social Capital in Shaping Europeans’ Immigration Sentiments","authors":"C. Economidou, D. Karamanis, Alexandra Kechrinioti, S. Xesfingi","doi":"10.2478/izajodm-2020-0003","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0003","url":null,"abstract":"Abstract Migration has manifested itself to historic highs, creating divisive views among politicians, policy makers, and individuals. The present paper studies the Europeans’ attitudes toward immigration, focusing particularly on the role of social capital. Based on 267,282 respondents from 22 countries and over the period 2002–2014, we find that despite the eventful past years, Europeans, on average, are positive toward immigrants with the North European countries to be the least xenophobic. A salient finding of our analysis is that regardless of the impact of other contextual factors, namely, a country’s macroeconomic conditions, ethnic diversity, cultural origin, and individuals’ attributes, social capital associates with positive attitudes toward all immigrants, independent of their background. Furthermore, social capital moderates the negative effects of perceived threat on people’s opinions about immigrants.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"46470805","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-2020-0018
O. Berisso, A. Heshmati
Abstract This paper does an empirical comparison of time-invariant and time-varying technical inefficiency measures obtained from an econometric estimation of different panel data stochastic production frontier models. It estimates four panel data specifications of frontier models widely used in empirical applications using a panel dataset from the Ethiopian cereal farming sector. The empirical results show that estimates of both the magnitude and the individual farms’ rankings of persistent and transient productive efficiencies differ considerably across models and based on their agro-ecological zones location. The results further show that the cereal growing farms experience much more transient inefficiency as compared to persistent inefficiency.
{"title":"Farm-heterogeneity and persistent and transient productive efficiencies in Ethiopia’s smallholder cereal farming","authors":"O. Berisso, A. Heshmati","doi":"10.2478/izajodm-2020-0018","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0018","url":null,"abstract":"Abstract This paper does an empirical comparison of time-invariant and time-varying technical inefficiency measures obtained from an econometric estimation of different panel data stochastic production frontier models. It estimates four panel data specifications of frontier models widely used in empirical applications using a panel dataset from the Ethiopian cereal farming sector. The empirical results show that estimates of both the magnitude and the individual farms’ rankings of persistent and transient productive efficiencies differ considerably across models and based on their agro-ecological zones location. The results further show that the cereal growing farms experience much more transient inefficiency as compared to persistent inefficiency.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44495349","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-2020-0020
J. Alonso, F. Arteaga
Abstract This article seeks to explain the contradiction between the promises of welfare gains derived from the economic models recommending the removal of immigration restrictions and the realities experienced by countries attempting to apply restrictions to immigration flows. A formal model is built in which the strategic reaction of countries considers not only the benefits derived from migration but also the (economic and non-economic) costs that migration can generate in the host country. Strategic reactions drive what may be called the “paradox of adverse interest”: the fewer potential gains associated with liberalization of migration, the easier it becomes for nations to reach an unrestrictive agreement. The existence of two asymmetries (between the bargaining power of receiving and sending countries, and between the private nature of most of migration’s benefits and the social nature of its main costs) can hinder the agreement when the countries involved exhibit a high wage differential. Results suggest that permissive international agreements on migration are easier to reach in regional contexts, among countries with proximate economic conditions and levels of income.
{"title":"International migratory agreements: the paradox of adverse interest","authors":"J. Alonso, F. Arteaga","doi":"10.2478/izajodm-2020-0020","DOIUrl":"https://doi.org/10.2478/izajodm-2020-0020","url":null,"abstract":"Abstract This article seeks to explain the contradiction between the promises of welfare gains derived from the economic models recommending the removal of immigration restrictions and the realities experienced by countries attempting to apply restrictions to immigration flows. A formal model is built in which the strategic reaction of countries considers not only the benefits derived from migration but also the (economic and non-economic) costs that migration can generate in the host country. Strategic reactions drive what may be called the “paradox of adverse interest”: the fewer potential gains associated with liberalization of migration, the easier it becomes for nations to reach an unrestrictive agreement. The existence of two asymmetries (between the bargaining power of receiving and sending countries, and between the private nature of most of migration’s benefits and the social nature of its main costs) can hinder the agreement when the countries involved exhibit a high wage differential. Results suggest that permissive international agreements on migration are easier to reach in regional contexts, among countries with proximate economic conditions and levels of income.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2020-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42180377","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 : 2019-12-01DOI: 10.1186/S40176-018-0138-2
C. Loschmann, Ö. Bilgili, M. Siegel
{"title":"Considering the benefits of hosting refugees: evidence of refugee camps influencing local labour market activity and economic welfare in Rwanda","authors":"C. Loschmann, Ö. Bilgili, M. Siegel","doi":"10.1186/S40176-018-0138-2","DOIUrl":"https://doi.org/10.1186/S40176-018-0138-2","url":null,"abstract":"","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":"9 1","pages":"1-23"},"PeriodicalIF":0.0,"publicationDate":"2019-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1186/S40176-018-0138-2","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41427682","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 : 2019-08-01DOI: 10.2478/izajodm-2019-0004
K. Hall, D. Posel
Abstract The disruption of family life is one of the important legacies of South Africa’s colonial and apartheid history. Families were undermined by deliberate strategies implemented through the pass laws, forced removals, urban housing policy, and the creation of homelands. Despite the removal of legal restrictions on permanent urban settlement and family co-residence for Africans, patterns of internal and oscillating labor migration have endured, dual or stretched households continue to link urban and rural nodes, children have remained less urbanized than adults, and many grow up without coresident parents. Although children are clearly affected by adult labor migration, they have tended to be ignored in the migration discourse. In this study, we add to the literature by showing how a child lens advances our understanding of the complexities of household arrangements and migration processes for families. In a mixed-methods study, we use nationally representative panel data to describe persistence, and also change, in migration patterns in South Africa when viewed from the perspective of children. We then draw on a detailed case study to explore what factors constrain or permit families to migrate together, or children to join adults at migration destination areas.
{"title":"Fragmenting the Family? The Complexity of Household Migration Strategies in Post-apartheid South Africa","authors":"K. Hall, D. Posel","doi":"10.2478/izajodm-2019-0004","DOIUrl":"https://doi.org/10.2478/izajodm-2019-0004","url":null,"abstract":"Abstract The disruption of family life is one of the important legacies of South Africa’s colonial and apartheid history. Families were undermined by deliberate strategies implemented through the pass laws, forced removals, urban housing policy, and the creation of homelands. Despite the removal of legal restrictions on permanent urban settlement and family co-residence for Africans, patterns of internal and oscillating labor migration have endured, dual or stretched households continue to link urban and rural nodes, children have remained less urbanized than adults, and many grow up without coresident parents. Although children are clearly affected by adult labor migration, they have tended to be ignored in the migration discourse. In this study, we add to the literature by showing how a child lens advances our understanding of the complexities of household arrangements and migration processes for families. In a mixed-methods study, we use nationally representative panel data to describe persistence, and also change, in migration patterns in South Africa when viewed from the perspective of children. We then draw on a detailed case study to explore what factors constrain or permit families to migrate together, or children to join adults at migration destination areas.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49227690","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 The possible nonlinearity of the income elasticity of child labor has been at the center of the debate regarding both its causes and the policy instruments to address it. We contribute to this debate providing theoretical and empirical novel results. From a theoretical point of view, for any given transfer size, there is a critical level of household income below which an increase in income has no impact on child labor and education. We estimate the causal impact of an increase in income on child labor and education exploiting the random allocation of the Child Grant Programme, an unconditional cash transfer (CT), in Lesotho. We show that the poorest households do not increase investment in children’s human capital, while relatively less poor households reduce child labor and increase education. In policy terms, the results indicate that CTs might not be always effective to support the investment in children’s human capital of the poorest households. Beside the integration with other measures, making the amount of transfer depends of the level of deprivation of the household, might improve CT effectiveness.
{"title":"Income Elasticity of Child Labor: Do Cash Transfers have an Impact on the Poorest Children?","authors":"Luca Pellerano, Eleonora Porreca, F. Rosati","doi":"10.2139/ssrn.3430439","DOIUrl":"https://doi.org/10.2139/ssrn.3430439","url":null,"abstract":"Abstract The possible nonlinearity of the income elasticity of child labor has been at the center of the debate regarding both its causes and the policy instruments to address it. We contribute to this debate providing theoretical and empirical novel results. From a theoretical point of view, for any given transfer size, there is a critical level of household income below which an increase in income has no impact on child labor and education. We estimate the causal impact of an increase in income on child labor and education exploiting the random allocation of the Child Grant Programme, an unconditional cash transfer (CT), in Lesotho. We show that the poorest households do not increase investment in children’s human capital, while relatively less poor households reduce child labor and increase education. In policy terms, the results indicate that CTs might not be always effective to support the investment in children’s human capital of the poorest households. Beside the integration with other measures, making the amount of transfer depends of the level of deprivation of the household, might improve CT effectiveness.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44503178","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 : 2019-06-01DOI: 10.2478/izajodm-2019-0007
Xuan Wei, Gülcan Önel, Zhengfei Guan, F. Roka
Abstract The policy debate surrounding the employment of immigrant workers in U.S. agriculture centers around the extent to which immigrant farmworkers adversely affect the economic opportunities of native farmworkers. To help answer this question, we propose a three-layer nested constant elasticity of substitution (CES) framework to investigate the substitutability among heterogeneous farmworker groups based on age, skill, and legal status utilizing National Agricultural Workers Survey (NAWS) data from 1989 through 2012. We use farmwork experience and type of task performed as alternative proxies for skill to disentangle the substitution effect between U.S. citizens, authorized immigrants, and unauthorized immigrant farmworkers. Results show that substitutability between the three legal status groups is small; neither authorized nor unauthorized immigrant farmworkers have a significant impact on the employment of native farmworkers.
{"title":"Substitution between Immigrant and Native Farmworkers in the United States: Does Legal Status Matter?","authors":"Xuan Wei, Gülcan Önel, Zhengfei Guan, F. Roka","doi":"10.2478/izajodm-2019-0007","DOIUrl":"https://doi.org/10.2478/izajodm-2019-0007","url":null,"abstract":"Abstract The policy debate surrounding the employment of immigrant workers in U.S. agriculture centers around the extent to which immigrant farmworkers adversely affect the economic opportunities of native farmworkers. To help answer this question, we propose a three-layer nested constant elasticity of substitution (CES) framework to investigate the substitutability among heterogeneous farmworker groups based on age, skill, and legal status utilizing National Agricultural Workers Survey (NAWS) data from 1989 through 2012. We use farmwork experience and type of task performed as alternative proxies for skill to disentangle the substitution effect between U.S. citizens, authorized immigrants, and unauthorized immigrant farmworkers. Results show that substitutability between the three legal status groups is small; neither authorized nor unauthorized immigrant farmworkers have a significant impact on the employment of native farmworkers.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48386063","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 : 2019-06-01DOI: 10.2478/izajodm-2019-0002
Yigit Aydede, Atul A. Dar
Abstract A growing wage gap between immigrant and native-born workers is well documented and is a fundamental policy issue in Canada. It is quite possible that wage differences, commonly attributed to the lower quality of foreign credentials or the deficiency in the accreditation of these credentials, merely reflect lower wage offers that immigrant workers receive due to risk aversion among local firms facing an elevated degree of asymmetric information. Using the 2006 and 2011 population censuses, this paper empirically investigates the effects of wage bargaining in labor markets on the wage gap between foreign- and Canadian-educated workers. Our results imply that a significant part of the wage gap between foreign-educated and Canadian-educated immigrant (and native-born) workers is not driven by the employers’ risk aversion but by differences in human capital endowments and occupational matching quality.
{"title":"Asymmetric Information and the Discount on Foreign-Acquired Degrees in Canada","authors":"Yigit Aydede, Atul A. Dar","doi":"10.2478/izajodm-2019-0002","DOIUrl":"https://doi.org/10.2478/izajodm-2019-0002","url":null,"abstract":"Abstract A growing wage gap between immigrant and native-born workers is well documented and is a fundamental policy issue in Canada. It is quite possible that wage differences, commonly attributed to the lower quality of foreign credentials or the deficiency in the accreditation of these credentials, merely reflect lower wage offers that immigrant workers receive due to risk aversion among local firms facing an elevated degree of asymmetric information. Using the 2006 and 2011 population censuses, this paper empirically investigates the effects of wage bargaining in labor markets on the wage gap between foreign- and Canadian-educated workers. Our results imply that a significant part of the wage gap between foreign-educated and Canadian-educated immigrant (and native-born) workers is not driven by the employers’ risk aversion but by differences in human capital endowments and occupational matching quality.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":"10 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42305550","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 : 2019-06-01DOI: 10.2478/izajodm-2019-0008
Dries Lens, I. Marx, S. Vujić
Abstract This paper examines the labor market trajectories of refugees who arrived in Belgium between 1999 and 2009. Belgium offers a relatively easy formal labor market access to refugees and other types of migrants but they face many other barriers in this strongly regulated and institutionalized labor market. Based on a longitudinal dataset that links respondents’ information from the Belgian Labor Force Survey with comprehensive social security data on their work histories, we estimate discrete-time hazard models to analyze refugees’ entry into and exit out of the first employment spell, contrasting their outcomes with family and labor migrants of the same arrival cohort. The analysis shows that refugees take significantly longer to enter their first employment spell as compared with other migrant groups. They also run a greater risk of exiting out of their first employment spell (back) into social assistance and into unemployment. The low employment rates of refugees are thus not only due to a slow integration process upon arrival, but also reflect a disproportional risk of exiting the labor market after a period in work. Our findings indicate that helping refugees into a first job is not sufficient to ensure labor market participation in the long run, because these jobs may be short-lived. Instead, our results provide clear arguments in favor of policies that support sustainable labor market integration.
{"title":"Double Jeopardy: How Refugees Fare in One European Labor Market","authors":"Dries Lens, I. Marx, S. Vujić","doi":"10.2478/izajodm-2019-0008","DOIUrl":"https://doi.org/10.2478/izajodm-2019-0008","url":null,"abstract":"Abstract This paper examines the labor market trajectories of refugees who arrived in Belgium between 1999 and 2009. Belgium offers a relatively easy formal labor market access to refugees and other types of migrants but they face many other barriers in this strongly regulated and institutionalized labor market. Based on a longitudinal dataset that links respondents’ information from the Belgian Labor Force Survey with comprehensive social security data on their work histories, we estimate discrete-time hazard models to analyze refugees’ entry into and exit out of the first employment spell, contrasting their outcomes with family and labor migrants of the same arrival cohort. The analysis shows that refugees take significantly longer to enter their first employment spell as compared with other migrant groups. They also run a greater risk of exiting out of their first employment spell (back) into social assistance and into unemployment. The low employment rates of refugees are thus not only due to a slow integration process upon arrival, but also reflect a disproportional risk of exiting the labor market after a period in work. Our findings indicate that helping refugees into a first job is not sufficient to ensure labor market participation in the long run, because these jobs may be short-lived. Instead, our results provide clear arguments in favor of policies that support sustainable labor market integration.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48955843","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 : 2019-06-01DOI: 10.2478/izajodm-2019-0003
Christopher Hoy, D. Naidoo
Abstract Policymakers typically try to address youth unemployment in developing countries through either active labor market programs (ALMPs) or labor-intensive public works programs (LIPWs). We examine whether there is any additional benefit for unemployed youth from participating in a comprehensive ALMP compared to a LIPW. We exploit an unanticipated intervention in the largest employment program in Papua New Guinea, which resulted in one intake of the program completing a LIPW and missing out on a comprehensive ALMP. We conduct a difference-in-difference analysis between participants in the intake that missed out on the ALMP component of the program and participants in the intakes immediately before and after. In contrast to most impact evaluations of ALMPs, we show youth that completed the comprehensive ALMP were around twice as likely to be employed in the formal sector 9–12 months after the program compared to similar youth in the intake that only completed a LIWP. This effect was entirely driven by 20% of youth who participated in the ALMP staying with the employer they were placed with following the end of the program. Surveys of these employers illustrate that they use the ALMP as a low-cost, low-risk, and relatively low-effort way of hiring new employees.
{"title":"The Marginal Benefit of an Active Labor Market Program Relative to a Public Works Program: Evidence from Papua New Guinea","authors":"Christopher Hoy, D. Naidoo","doi":"10.2478/izajodm-2019-0003","DOIUrl":"https://doi.org/10.2478/izajodm-2019-0003","url":null,"abstract":"Abstract Policymakers typically try to address youth unemployment in developing countries through either active labor market programs (ALMPs) or labor-intensive public works programs (LIPWs). We examine whether there is any additional benefit for unemployed youth from participating in a comprehensive ALMP compared to a LIPW. We exploit an unanticipated intervention in the largest employment program in Papua New Guinea, which resulted in one intake of the program completing a LIPW and missing out on a comprehensive ALMP. We conduct a difference-in-difference analysis between participants in the intake that missed out on the ALMP component of the program and participants in the intakes immediately before and after. In contrast to most impact evaluations of ALMPs, we show youth that completed the comprehensive ALMP were around twice as likely to be employed in the formal sector 9–12 months after the program compared to similar youth in the intake that only completed a LIWP. This effect was entirely driven by 20% of youth who participated in the ALMP staying with the employer they were placed with following the end of the program. Surveys of these employers illustrate that they use the ALMP as a low-cost, low-risk, and relatively low-effort way of hiring new employees.","PeriodicalId":37475,"journal":{"name":"IZA Journal of Development and Migration","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2019-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48932776","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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