We employ the original Card and Krueger (1994) data and the CIC estimator to reexamine the evidence on the effect of minimum wages on employment. Our main finding is that the controversial result remains valid only for small fast-food restaurants. This finding is accompanied with a new possible explanation.
{"title":"Minimum Wages and Employment: Replication of Card and Krueger (1994) Using the CIC Estimator","authors":"O. Ropponen","doi":"10.2139/ssrn.1586327","DOIUrl":"https://doi.org/10.2139/ssrn.1586327","url":null,"abstract":"We employ the original Card and Krueger (1994) data and the CIC estimator to reexamine the evidence on the effect of minimum wages on employment. Our main finding is that the controversial result remains valid only for small fast-food restaurants. This finding is accompanied with a new possible explanation.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125863511","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 investigates the impact of legalization on the economic outcomes of the legalized population. It uses a natural experiment caused by the 1986 Immigration Reform and Control Act (IRCA) which gave amnesty for undocumented immigrants who could prove continuous residence in the U.S. after January 1, 1982. The arbitrary cutoff date on the eligibility criteria causes a discontinuity in the relationship between the year of immigration and the probability of being legal. This paper uses this discontinuity to identify the causal impacts of legalization on immigrants’ outcomes. Regression discontinuity and difference-in-differences estimates show that immigrants eligible for the policy have a significantly higher probability of being naturalized citizens than those who were not. Legalization is also found to have a positive and significant effect on wages, a negative effect on the probability of working in a traditionally illegal occupation, and no significant effect on geographical mobility. The analysis for different demographic groups confirms such conclusions and shows that the estimated effects of legalization are larger for low-educated Latin American immigrants, the group that was disproportionably affected by the policy.
{"title":"Legalization and the Economic Status of Immigrants","authors":"S. Barcellos","doi":"10.2139/ssrn.1604230","DOIUrl":"https://doi.org/10.2139/ssrn.1604230","url":null,"abstract":"This paper investigates the impact of legalization on the economic outcomes of the legalized population. It uses a natural experiment caused by the 1986 Immigration Reform and Control Act (IRCA) which gave amnesty for undocumented immigrants who could prove continuous residence in the U.S. after January 1, 1982. The arbitrary cutoff date on the eligibility criteria causes a discontinuity in the relationship between the year of immigration and the probability of being legal. This paper uses this discontinuity to identify the causal impacts of legalization on immigrants’ outcomes. Regression discontinuity and difference-in-differences estimates show that immigrants eligible for the policy have a significantly higher probability of being naturalized citizens than those who were not. Legalization is also found to have a positive and significant effect on wages, a negative effect on the probability of working in a traditionally illegal occupation, and no significant effect on geographical mobility. The analysis for different demographic groups confirms such conclusions and shows that the estimated effects of legalization are larger for low-educated Latin American immigrants, the group that was disproportionably affected by the policy.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-03-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124716986","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}
In this paper we show that wage inequality decreased in the Italian private sector, both in the upper and in the lower tail of the distribution, in the period 1993-2006. By applying a quantile decomposition procedure we find that the decrease of the 90/50 ratio is almost totally related to a negative coefficients component. As for the reduction of the 50/10 ratio, the quantile decomposition shows that it can be related to both the negative coefficients component and the residual component. We claim that that supply and demand for education have to be considered as the main explanation for the falling educational wage premia that represent the driving force of the falling 90/50 ratio. The reduction of the 50/10 ratio can be instead associated to the changes in the residual component -related to compositional effects-, to the changes in the occupation distribution and to changes in tax regimes.
{"title":"Decreasing Wage Inequality in Italy: The Role of Supply and Demand for Education","authors":"Paolo Naticchioni, A. Ricci","doi":"10.2139/ssrn.1548633","DOIUrl":"https://doi.org/10.2139/ssrn.1548633","url":null,"abstract":"In this paper we show that wage inequality decreased in the Italian private sector, both in the upper and in the lower tail of the distribution, in the period 1993-2006. By applying a quantile decomposition procedure we find that the decrease of the 90/50 ratio is almost totally related to a negative coefficients component. As for the reduction of the 50/10 ratio, the quantile decomposition shows that it can be related to both the negative coefficients component and the residual component. We claim that that supply and demand for education have to be considered as the main explanation for the falling educational wage premia that represent the driving force of the falling 90/50 ratio. The reduction of the 50/10 ratio can be instead associated to the changes in the residual component -related to compositional effects-, to the changes in the occupation distribution and to changes in tax regimes.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2010-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120978348","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 rural poor in developing countries have great difficulty in coping with adverse weather. In theory, workfare programs may serve as an important mechanism for allowing households to deal with the effects of weather related shocks. If participation in a workfare program is sufficiently flexible households in a village which suffers bad weather may compensate for the loss of income by increasing their participation in the program. If participation in a workfare program is not sufficiently flexible due to, for example, caps on overall participation at the local level, then the program will not allow households to compensate for the effects of a weather shock. We evaluate whether India’s new workfare program for rural areas, the National Rural Employment Guarantee Act (NREGA), allowed households in one state to mitigate the effects of weather induced income shocks by looking at whether NREGA participation is responsive to changes in rainfall. We find that NREGA did allow households to mitigate the effects of weather induced income shocks. While we are unable to precisely identify the relationship between changes in income and participation in NREGA, we show that the relationship is strong enough to be practically significant.
{"title":"Can Workfare Serve as a Substitute for Weather Insurance? The Case of NREGA in Andhra Pradesh","authors":"Doug Johnson","doi":"10.2139/ssrn.1664160","DOIUrl":"https://doi.org/10.2139/ssrn.1664160","url":null,"abstract":"The rural poor in developing countries have great difficulty in coping with adverse weather. In theory, workfare programs may serve as an important mechanism for allowing households to deal with the effects of weather related shocks. If participation in a workfare program is sufficiently flexible households in a village which suffers bad weather may compensate for the loss of income by increasing their participation in the program. If participation in a workfare program is not sufficiently flexible due to, for example, caps on overall participation at the local level, then the program will not allow households to compensate for the effects of a weather shock. We evaluate whether India’s new workfare program for rural areas, the National Rural Employment Guarantee Act (NREGA), allowed households in one state to mitigate the effects of weather induced income shocks by looking at whether NREGA participation is responsive to changes in rainfall. We find that NREGA did allow households to mitigate the effects of weather induced income shocks. While we are unable to precisely identify the relationship between changes in income and participation in NREGA, we show that the relationship is strong enough to be practically significant.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-12-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123783198","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 shows that a temporary incentive to join the labor market or to work more can also produce substantial life-cycle labor supply effects. On September 1997, a new childcare policy was initiated by the provincial government of Quebec, the second most populous province in Canada. Licensed and regulated providers of childcare services began offering day care spaces at the subsidized fee of $5 per day per child for children aged 4. In successive years, the government reduced the age requirement, created new childcare facilities and spaces, and paid for the additional costs entailed by this low-fee policy. No such important policy changes for preschool (including kindergarten) children were enacted in the nine other Canadian provinces over the years 1997 to 2004. Using annual data drawn from Statistics Canada's Survey on Labour and Income Dynamic and a difference-in-differences quasi experimental methodology, the paper estimates the dynamic labor supply effects of the program. The results demonstrate that the policy had long-term labor supply effects on mothers who benefited from the program when their child was less than 6. A striking feature of the results is that they are driven by changes in the labor supply of less educated mothers.
{"title":"Dynamic Labour Supply Effects of Childcare Subsidies: Evidence from a Canadian Natural Experiment on Low-Fee Universal Child Care","authors":"P. Lefèbvre, P. Merrigan, Matthieu Verstraete","doi":"10.2139/ssrn.1279674","DOIUrl":"https://doi.org/10.2139/ssrn.1279674","url":null,"abstract":"This paper shows that a temporary incentive to join the labor market or to work more can also produce substantial life-cycle labor supply effects. On September 1997, a new childcare policy was initiated by the provincial government of Quebec, the second most populous province in Canada. Licensed and regulated providers of childcare services began offering day care spaces at the subsidized fee of $5 per day per child for children aged 4. In successive years, the government reduced the age requirement, created new childcare facilities and spaces, and paid for the additional costs entailed by this low-fee policy. No such important policy changes for preschool (including kindergarten) children were enacted in the nine other Canadian provinces over the years 1997 to 2004. Using annual data drawn from Statistics Canada's Survey on Labour and Income Dynamic and a difference-in-differences quasi experimental methodology, the paper estimates the dynamic labor supply effects of the program. The results demonstrate that the policy had long-term labor supply effects on mothers who benefited from the program when their child was less than 6. A striking feature of the results is that they are driven by changes in the labor supply of less educated mothers.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128311754","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}
Arguments for increasing access to knowledge have generally been concerned with rights. In the developing context, increased access to knowledge also has strong economic and developmental benefits. An emergent access to learning materials movement in South Africa has the opportunity to make use of both kinds of argument. The South African education system is currently deficient in several ways, and some of these deficiencies arise from lack of access to appropriate learning materials. This paper reviews some of the arguments put forward by the access to learning materials movement in favour of increasing access to knowledge and reforming the South African intellectual property law framework. These arguments and potential constitutional arguments for increasing access will be strengthened by the availability of empirical evidence about the economic benefits of alternative intellectual property policies. It is argued that further research of this nature should be undertaken.
{"title":"Access to Learning Materials in South Africa: The Convergence of Developmental and Rights-Based Arguments for Access to Knowledge","authors":"J. Jonker","doi":"10.2139/ssrn.1455943","DOIUrl":"https://doi.org/10.2139/ssrn.1455943","url":null,"abstract":"Arguments for increasing access to knowledge have generally been concerned with rights. In the developing context, increased access to knowledge also has strong economic and developmental benefits. An emergent access to learning materials movement in South Africa has the opportunity to make use of both kinds of argument. The South African education system is currently deficient in several ways, and some of these deficiencies arise from lack of access to appropriate learning materials. This paper reviews some of the arguments put forward by the access to learning materials movement in favour of increasing access to knowledge and reforming the South African intellectual property law framework. These arguments and potential constitutional arguments for increasing access will be strengthened by the availability of empirical evidence about the economic benefits of alternative intellectual property policies. It is argued that further research of this nature should be undertaken.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115320928","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 chapter proposes three criteria for comparative evaluation of repayment forms of consumer bankruptcy around the world: creditor repayment net of administrative costs, rates of discharge, and treatment (particularly as judged by whether debtors have debt problems again). It also argues that rational sorting reconciles these three goals to the extent possible. After marshalling available data from North America, Australia and Europe, the chapter concludes that repayment bankruptcy options in all these regions of the world appear to have high costs in relation to unsecured debt repayment and significant rates of failure to achieve a discharge. A glaring hole in our knowledge is whether repayment options treat the problem of overindebtedness or instead leave many debtors still struggling financially and perhaps in other ways, too. All systems seems to have sorting problems, with many low income debtors attempting and failing to complete plans, meaning they repay little or nothing but are nonetheless delayed in getting a discharge and in starting on the road to a sound financial future. Further empirical investigation is needed to evaluate systems in terms of results rather than aspirations, the essence of a law-in-action perspective.
{"title":"A Law-in-Action Approach to Comparative Study of Repayment Forms of Consumer Bankruptcy","authors":"J. Braucher","doi":"10.2139/SSRN.1116011","DOIUrl":"https://doi.org/10.2139/SSRN.1116011","url":null,"abstract":"This chapter proposes three criteria for comparative evaluation of repayment forms of consumer bankruptcy around the world: creditor repayment net of administrative costs, rates of discharge, and treatment (particularly as judged by whether debtors have debt problems again). It also argues that rational sorting reconciles these three goals to the extent possible. After marshalling available data from North America, Australia and Europe, the chapter concludes that repayment bankruptcy options in all these regions of the world appear to have high costs in relation to unsecured debt repayment and significant rates of failure to achieve a discharge. A glaring hole in our knowledge is whether repayment options treat the problem of overindebtedness or instead leave many debtors still struggling financially and perhaps in other ways, too. All systems seems to have sorting problems, with many low income debtors attempting and failing to complete plans, meaning they repay little or nothing but are nonetheless delayed in getting a discharge and in starting on the road to a sound financial future. Further empirical investigation is needed to evaluate systems in terms of results rather than aspirations, the essence of a law-in-action perspective.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114986747","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 'rule of law' has traditionally been conceived as an intrinsically positive and politically neutral 'tool', universally valid and capable of being 'exported' everywhere. This paper - which represents a synthetic exposition of the ideas expressed in Ugo Mattei and Laura Nader, Plunder: When the Rule of Law is Illegal (Blackwell Publishing, Oxford 2008) - asserts that such an ambiguous concept has a bright and a dark side, the latter being excluded from any public discussion. The rhetoric of the 'rule of law' has been used by Western powers in order to justify interventions (mainly) into the 'developing' world, that ultimately turned into practices of plunder, allowing the expansion of Western economic power over the 'rest', thus backing a claim that the rule of law has been used 'illegally'. Intellectual myopia, ethnocentrism and imperial attitudes stand behind the conception of the rule of law that currently wraps international financial institutions - today’s global legislators - reform projects in the 'developing world'. The transformation of the concept of ‘law’ into that of a 'technicality', the globally dominant position enjoyed by U.S. law and the imperial attitude of today’s Western international corporate actors are some of the elements that show a pattern of continuity between colonialism and today's neo-liberal policy.
{"title":"Global Law and Plunder: The Dark Side of the Rule of Law","authors":"U. Mattei, M. de Morpurgo","doi":"10.2139/ssrn.1437530","DOIUrl":"https://doi.org/10.2139/ssrn.1437530","url":null,"abstract":"The 'rule of law' has traditionally been conceived as an intrinsically positive and politically neutral 'tool', universally valid and capable of being 'exported' everywhere. This paper - which represents a synthetic exposition of the ideas expressed in Ugo Mattei and Laura Nader, Plunder: When the Rule of Law is Illegal (Blackwell Publishing, Oxford 2008) - asserts that such an ambiguous concept has a bright and a dark side, the latter being excluded from any public discussion. The rhetoric of the 'rule of law' has been used by Western powers in order to justify interventions (mainly) into the 'developing' world, that ultimately turned into practices of plunder, allowing the expansion of Western economic power over the 'rest', thus backing a claim that the rule of law has been used 'illegally'. Intellectual myopia, ethnocentrism and imperial attitudes stand behind the conception of the rule of law that currently wraps international financial institutions - today’s global legislators - reform projects in the 'developing world'. The transformation of the concept of ‘law’ into that of a 'technicality', the globally dominant position enjoyed by U.S. law and the imperial attitude of today’s Western international corporate actors are some of the elements that show a pattern of continuity between colonialism and today's neo-liberal policy.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-07-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126614850","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}
In recent years, a number of governments and consumer groups in rich countries have tried to discourage the use of child labor in poor countries through measures such as product boycotts and the imposition of international labor standards. The purported objective of such measures is to reduce the incidence of child labor in developing countries and thereby improve children's welfare. In this paper, we examine the effects of such policies from a political-economy perspective. We show that these types of international action on child labor tend to lower domestic political support within developing countries for banning child labor. Hence, international labor standards and product boycotts may delay the ultimate eradication of child labor.
{"title":"Do International Labor Standards Contribute to the Persistence of the Child Labor Problem?","authors":"Matthias Doepke, Fabrizio Zilibotti","doi":"10.2139/ssrn.1554814","DOIUrl":"https://doi.org/10.2139/ssrn.1554814","url":null,"abstract":"In recent years, a number of governments and consumer groups in rich countries have tried to discourage the use of child labor in poor countries through measures such as product boycotts and the imposition of international labor standards. The purported objective of such measures is to reduce the incidence of child labor in developing countries and thereby improve children's welfare. In this paper, we examine the effects of such policies from a political-economy perspective. We show that these types of international action on child labor tend to lower domestic political support within developing countries for banning child labor. Hence, international labor standards and product boycotts may delay the ultimate eradication of child labor.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"8 5","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"113956686","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}
In this paper, we conduct the novel exercise of analyzing the relationship between overall wealth inequality and caste divisions in India using nationally representative surveys on household wealth conducted during 1991–92 and 2002–03. According to our findings, the groups in India that are generally considered disadvantaged (known as Scheduled Castes or Scheduled Tribes) have, as one would expect, substantially lower wealth than the "forward" caste groups, while the Other Backward Classes and non-Hindus occupy positions in the middle. Using the ANOGI decomposition technique, we estimate that between-caste inequality accounted for about 13 percent of overall wealth inequality in 2002–03, in part due to the considerable heterogeneity within the broadly defined caste groups. The stratification parameters indicate that the forward caste Hindus overlap little with the other caste groups, while the latter have significantly higher degrees of overlap with one another and with the overall population. Using this method, we are also able to comment on the emergence and strengthening of a "creamy layer," or relatively well-off group, among the disadvantaged castes, especially the Scheduled Tribes.
{"title":"Caste and Wealth Inequality in India","authors":"Ajit Zacharias, V. Vakulabharanam","doi":"10.2139/ssrn.1410660","DOIUrl":"https://doi.org/10.2139/ssrn.1410660","url":null,"abstract":"In this paper, we conduct the novel exercise of analyzing the relationship between overall wealth inequality and caste divisions in India using nationally representative surveys on household wealth conducted during 1991–92 and 2002–03. According to our findings, the groups in India that are generally considered disadvantaged (known as Scheduled Castes or Scheduled Tribes) have, as one would expect, substantially lower wealth than the \"forward\" caste groups, while the Other Backward Classes and non-Hindus occupy positions in the middle. Using the ANOGI decomposition technique, we estimate that between-caste inequality accounted for about 13 percent of overall wealth inequality in 2002–03, in part due to the considerable heterogeneity within the broadly defined caste groups. The stratification parameters indicate that the forward caste Hindus overlap little with the other caste groups, while the latter have significantly higher degrees of overlap with one another and with the overall population. Using this method, we are also able to comment on the emergence and strengthening of a \"creamy layer,\" or relatively well-off group, among the disadvantaged castes, especially the Scheduled Tribes.","PeriodicalId":306856,"journal":{"name":"Economic Inequality & the Law eJournal","volume":"129 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2009-05-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127029228","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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