Stochastic earnings frontiers have been used in a relatively small number of papers to analyse workers' ability to capture their full potential earnings in labour markets where there is inefficient job matching (due to lack of information, discrimination, over-education or during process of assimilation of migrants). Using a representative survey of young persons having left full-time education in France in 1998 and interviewed in 2001 and 2005, this paper examines the process of their assimilation into normal employment and the extent to which job matches are inefficient in the sense that the pay in a job is below an individual's potential earnings (determined by education, other forms of training and labour market experience). Our results suggest that young workers manage to obtain on average about 82% of their potential earnings three years after leaving full-time education and earnings inefficiency had disappeared four years later. The results are robust to the treatment of selectivity arising from the exclusion of the unemployed in the estimation of the frontier.
{"title":"The Assimilation of Young Workers into the Labour Market in France: A Stochastic Earnings Frontier Approach","authors":"S. Bazen, K. Waziri","doi":"10.2139/ssrn.2998950","DOIUrl":"https://doi.org/10.2139/ssrn.2998950","url":null,"abstract":"Stochastic earnings frontiers have been used in a relatively small number of papers to analyse workers' ability to capture their full potential earnings in labour markets where there is inefficient job matching (due to lack of information, discrimination, over-education or during process of assimilation of migrants). Using a representative survey of young persons having left full-time education in France in 1998 and interviewed in 2001 and 2005, this paper examines the process of their assimilation into normal employment and the extent to which job matches are inefficient in the sense that the pay in a job is below an individual's potential earnings (determined by education, other forms of training and labour market experience). Our results suggest that young workers manage to obtain on average about 82% of their potential earnings three years after leaving full-time education and earnings inefficiency had disappeared four years later. The results are robust to the treatment of selectivity arising from the exclusion of the unemployed in the estimation of the frontier.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"357 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122721030","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 : 2017-06-22DOI: 10.1093/oso/9780198829591.003.0016
S. Joshi, Nishtha Kochhar, V. Rao
Indian society is highly stratified and hierarchical. Caste, class, and gender all contribute to an individual’s status. A large body of literature explores the importance of each of these. This chapter examines the relationship between caste and gender inequality in three states in India. When households are grouped using conventional, government-defined categories of caste, we find patterns that are consistent with existing literature: lower-caste women are more likely to participate in the labour market, have greater decision making autonomy within their households, and experience greater freedom of movement. When households are grouped by the narrower sub-caste categories of jati, where caste is lived and experienced, we find the relationships are far more varied and nuanced. These results suggest that focusing on broad caste categories such as ‘scheduled castes’ and ‘scheduled tribes’ can be misleading for understanding the relationship between caste and gender.
{"title":"Are Caste Categories Misleading? The Relationship between Gender and Jati in Three Indian States","authors":"S. Joshi, Nishtha Kochhar, V. Rao","doi":"10.1093/oso/9780198829591.003.0016","DOIUrl":"https://doi.org/10.1093/oso/9780198829591.003.0016","url":null,"abstract":"Indian society is highly stratified and hierarchical. Caste, class, and gender all contribute to an individual’s status. A large body of literature explores the importance of each of these. This chapter examines the relationship between caste and gender inequality in three states in India. When households are grouped using conventional, government-defined categories of caste, we find patterns that are consistent with existing literature: lower-caste women are more likely to participate in the labour market, have greater decision making autonomy within their households, and experience greater freedom of movement. When households are grouped by the narrower sub-caste categories of jati, where caste is lived and experienced, we find the relationships are far more varied and nuanced. These results suggest that focusing on broad caste categories such as ‘scheduled castes’ and ‘scheduled tribes’ can be misleading for understanding the relationship between caste and gender.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"11 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127333508","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}
I exploit heterogeneous impulse responses at the household level due to limited stock market participation to provide novel evidence on the degree of nominal rigidities. A number of studies show that positive technology shocks reduce aggregate hours. The finding is often interpreted as evidence in favor of sticky prices. Using the Consumer Expenditure Survey, I show that, while non-stockholders reduce hours in response to a positive technology shock, stockholders increase them. Aggregate hours fall because most households are non-stockholders. This finding is inconsistent with models featuring a high degree of nominal rigidities. (Copyright: Elsevier)
{"title":"Technology Shocks and Hours Revisited: Evidence from Household Data","authors":"Hikaru Saijo","doi":"10.2139/ssrn.2934644","DOIUrl":"https://doi.org/10.2139/ssrn.2934644","url":null,"abstract":"I exploit heterogeneous impulse responses at the household level due to limited stock market participation to provide novel evidence on the degree of nominal rigidities. A number of studies show that positive technology shocks reduce aggregate hours. The finding is often interpreted as evidence in favor of sticky prices. Using the Consumer Expenditure Survey, I show that, while non-stockholders reduce hours in response to a positive technology shock, stockholders increase them. Aggregate hours fall because most households are non-stockholders. This finding is inconsistent with models featuring a high degree of nominal rigidities. (Copyright: Elsevier)","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124606309","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 examines the exposure, vulnerability, and ability of households in Colombo, Sri Lanka, to respond to floods, and brings out significant policy implications. The study used detailed questionnaire-based surveys to obtain data on households, to understand the vulnerability and impacts of the severe floods of November 2010 and recurrent floods since then. Households that were selected for the surveys were located in and around flooding spots in the city. The study finds that the floods have imposed a significant burden on poor households. Poor and nonpoor households have suffered damages to the structure of their houses, household assets and appliances, and vehicles. With recurrent floods, they continue to bear the cost of damages as well as short-term measures to cope with floods. For poor families, these costs are borne through very limited resources and borrowing from informal sources, compared with the nonpoor who have more savings in financial form and greater access to formal sources of credit. Poor families tend to invest all their earnings in their home, furniture, and utensils, which suffer the most during floods. In addition, households suffer indirect impacts due to non-availability of transport, power, drinking water, food, and essential supplies. They also tend to lose workdays, which leads to loss of income and productivity. Many poor families have considered relocation to flood-free areas, but they lack the financial resources for the move. If the government offers such a scheme, many would be willing to take it up, if factors like job opportunities, clean surroundings, access to medical facilities, transportation, and good social networks are ensured in the new locations.
{"title":"Colombo: Exposure, Vulnerability, and Ability to Respond to Floods","authors":"A. Patankar","doi":"10.1596/1813-9450-8084","DOIUrl":"https://doi.org/10.1596/1813-9450-8084","url":null,"abstract":"This paper examines the exposure, vulnerability, and ability of households in Colombo, Sri Lanka, to respond to floods, and brings out significant policy implications. The study used detailed questionnaire-based surveys to obtain data on households, to understand the vulnerability and impacts of the severe floods of November 2010 and recurrent floods since then. Households that were selected for the surveys were located in and around flooding spots in the city. The study finds that the floods have imposed a significant burden on poor households. Poor and nonpoor households have suffered damages to the structure of their houses, household assets and appliances, and vehicles. With recurrent floods, they continue to bear the cost of damages as well as short-term measures to cope with floods. For poor families, these costs are borne through very limited resources and borrowing from informal sources, compared with the nonpoor who have more savings in financial form and greater access to formal sources of credit. Poor families tend to invest all their earnings in their home, furniture, and utensils, which suffer the most during floods. In addition, households suffer indirect impacts due to non-availability of transport, power, drinking water, food, and essential supplies. They also tend to lose workdays, which leads to loss of income and productivity. Many poor families have considered relocation to flood-free areas, but they lack the financial resources for the move. If the government offers such a scheme, many would be willing to take it up, if factors like job opportunities, clean surroundings, access to medical facilities, transportation, and good social networks are ensured in the new locations.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"58 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124367723","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper documents the main channel through which credit booms affect real economic activity in the future. As a matter of simple accounting, credit booms generate a predictable increase in future debt service that transfers spending power from borrowers to lenders. We document this dynamic pattern in a panel of 17 countries from 1980 to 2015 and identify a robust lead-lag relationship of about 3 years between the peak of credit booms and the peak in debt service. We develop a method to decompose what fraction of future real effects of credit booms is explained by debt service and show that debt service almost fully accounts for several puzzling findings in the recent empirical literature: that high growth in credit predicts low output growth in the future, deeper recessions, and a greater likelihood of financial crises. Explicitly accounting for debt service not only sheds light on the channel behind these findings but also generates stronger empirical relationships. We hope that our results will provide useful guidance for future efforts to model credit cycles.
{"title":"Accounting for Debt Service: The Painful Legacy of Credit Booms","authors":"Mathias Drehmann, M. Juselius, Anton Korinek","doi":"10.2139/ssrn.2993859","DOIUrl":"https://doi.org/10.2139/ssrn.2993859","url":null,"abstract":"This paper documents the main channel through which credit booms affect real economic activity in the future. As a matter of simple accounting, credit booms generate a predictable increase in future debt service that transfers spending power from borrowers to lenders. We document this dynamic pattern in a panel of 17 countries from 1980 to 2015 and identify a robust lead-lag relationship of about 3 years between the peak of credit booms and the peak in debt service. We develop a method to decompose what fraction of future real effects of credit booms is explained by debt service and show that debt service almost fully accounts for several puzzling findings in the recent empirical literature: that high growth in credit predicts low output growth in the future, deeper recessions, and a greater likelihood of financial crises. Explicitly accounting for debt service not only sheds light on the channel behind these findings but also generates stronger empirical relationships. We hope that our results will provide useful guidance for future efforts to model credit cycles.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"124 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114990748","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 examines the long-term effects of extended unemployment benefits that older unemployed can collect until retirement in Finland. We consider a reform that increased the age threshold of this scheme from 55 to 57 for people born in 1950 or later. Our regression discontinuity estimates show that postponing eligibility by two years increased employment over the remaining working career by seven months. Despite the corresponding reduction in unemployment, we find no evidence of significant effects on mortality or receipt of disability and sickness benefits, nor on the spouse's labor supply. We also compute the fiscal impact of the reform taking into account income taxes and social security contributions paid and benefits received. The reform increased net income transfers by 15,000 Euros over the 10-year period for an average individual.
{"title":"Long-Term Effects of Extended Unemployment Benefits for Older Workers","authors":"Tomi Kyyrä, Hanna Pesola","doi":"10.2139/ssrn.2977893","DOIUrl":"https://doi.org/10.2139/ssrn.2977893","url":null,"abstract":"This paper examines the long-term effects of extended unemployment benefits that older unemployed can collect until retirement in Finland. We consider a reform that increased the age threshold of this scheme from 55 to 57 for people born in 1950 or later. Our regression discontinuity estimates show that postponing eligibility by two years increased employment over the remaining working career by seven months. Despite the corresponding reduction in unemployment, we find no evidence of significant effects on mortality or receipt of disability and sickness benefits, nor on the spouse's labor supply. We also compute the fiscal impact of the reform taking into account income taxes and social security contributions paid and benefits received. The reform increased net income transfers by 15,000 Euros over the 10-year period for an average individual.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-05-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128587569","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}
D. Epple, R. Romano, Sinan Sarpça, Holger Sieg, Melanie A Zaber
The main purpose of this paper is to estimate an equilibrium model of private and public school competition that can generate realistic pricing patterns for private universities in the U.S. We show that the parameters of the model are identified and can be estimated using a semi-parametric estimator given data from the NPSAS. We find substantial price discrimination within colleges. We estimate that a $10,000 increase in family income increases tuition at private schools by on average $210 to $510. A one standard deviation increase in ability decreases tuition by approximately $920 to $1,960 depending on the selectivity of the college. Discounts for minority students range between $110 and $5,750.
{"title":"Market Power and Price Discrimination in the U.S. Market for Higher Education","authors":"D. Epple, R. Romano, Sinan Sarpça, Holger Sieg, Melanie A Zaber","doi":"10.1111/1756-2171.12267","DOIUrl":"https://doi.org/10.1111/1756-2171.12267","url":null,"abstract":"The main purpose of this paper is to estimate an equilibrium model of private and public school competition that can generate realistic pricing patterns for private universities in the U.S. We show that the parameters of the model are identified and can be estimated using a semi-parametric estimator given data from the NPSAS. We find substantial price discrimination within colleges. We estimate that a $10,000 increase in family income increases tuition at private schools by on average $210 to $510. A one standard deviation increase in ability decreases tuition by approximately $920 to $1,960 depending on the selectivity of the college. Discounts for minority students range between $110 and $5,750.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117029013","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}
Olivier Coibion, Y. Gorodnichenko, Dmitri K. Koustas
We document a decline in the frequency of shopping trips in the United States since 1980 and consider its implications for the measurement of consumption inequality. A decline in shopping frequency as households stock up on storable goods (i.e., inventory behavior) will lead to a rise in expenditure inequality when the latter is measured at high frequency, even when underlying consumption inequality is unchanged. We find that most of the recently documented rise in expenditure inequality in the United States since the 1980s can be accounted for by this phenomenon. Using detailed micro data on spending, which we link to data on club/warehouse store openings, we directly attribute much of the reduced frequency of shopping trips to the rise in club/warehouse stores. (JEL D12, D31, D63, D91, E21)
{"title":"Consumption Inequality and the Frequency of Purchases","authors":"Olivier Coibion, Y. Gorodnichenko, Dmitri K. Koustas","doi":"10.1257/MAC.20190115","DOIUrl":"https://doi.org/10.1257/MAC.20190115","url":null,"abstract":"We document a decline in the frequency of shopping trips in the United States since 1980 and consider its implications for the measurement of consumption inequality. A decline in shopping frequency as households stock up on storable goods (i.e., inventory behavior) will lead to a rise in expenditure inequality when the latter is measured at high frequency, even when underlying consumption inequality is unchanged. We find that most of the recently documented rise in expenditure inequality in the United States since the 1980s can be accounted for by this phenomenon. Using detailed micro data on spending, which we link to data on club/warehouse store openings, we directly attribute much of the reduced frequency of shopping trips to the rise in club/warehouse stores. (JEL D12, D31, D63, D91, E21)","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"117 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-04-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124144555","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}
Over the past two decades, crime has fallen dramatically in cities in the United States. We explore whether, in the face of falling central city crime rates, households with more resources and options were more likely to move into central cities overall and more particularly into low income and/or majority minority central city neighborhoods. We use confidential, geocoded versions of the 1990 and 2000 Decennial Census and the 2010, 2011, and 2012 American Community Survey to track moves to different neighborhoods in 244 Core Based Statistical Areas (CBSAs) and their largest central cities. Our dataset includes over four million household moves across the three time periods. We focus on three household types typically considered gentrifiers: high-income, college-educated, and white households. We find that declines in city crime are associated with increases in the probability that highincome and college-educated households choose to move into central city neighborhoods, including low-income and majority minority central city neighborhoods. Moreover, we find little evidence that households with lower incomes and without college degrees are more likely to move to cities when violent crime falls. These results hold during the 1990s as well as the 2000s and for the 100 largest metropolitan areas, where crime declines were greatest. There is weaker evidence that white households are disproportionately drawn to cities as crime falls in the 100 largest metropolitan areas from 2000 to 2010.
{"title":"Has Falling Crime Invited Gentrification?","authors":"I. Ellen, Keren Mertens Horn, D. Reed","doi":"10.2139/ssrn.2930242","DOIUrl":"https://doi.org/10.2139/ssrn.2930242","url":null,"abstract":"Over the past two decades, crime has fallen dramatically in cities in the United States. We explore whether, in the face of falling central city crime rates, households with more resources and options were more likely to move into central cities overall and more particularly into low income and/or majority minority central city neighborhoods. We use confidential, geocoded versions of the 1990 and 2000 Decennial Census and the 2010, 2011, and 2012 American Community Survey to track moves to different neighborhoods in 244 Core Based Statistical Areas (CBSAs) and their largest central cities. Our dataset includes over four million household moves across the three time periods. We focus on three household types typically considered gentrifiers: high-income, college-educated, and white households. We find that declines in city crime are associated with increases in the probability that highincome and college-educated households choose to move into central city neighborhoods, including low-income and majority minority central city neighborhoods. Moreover, we find little evidence that households with lower incomes and without college degrees are more likely to move to cities when violent crime falls. These results hold during the 1990s as well as the 2000s and for the 100 largest metropolitan areas, where crime declines were greatest. There is weaker evidence that white households are disproportionately drawn to cities as crime falls in the 100 largest metropolitan areas from 2000 to 2010.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121700094","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}
Household survey data provide a rich information set on income, household context and demographic variables, but tend to under report incomes at the very top of the distribution. Administrative data like tax records offer more precise information on top incomes, but at the expense of household context details and incomes of non-filers at the bottom of the distribution. We combine the benefits of the two data sources and develop an integrated approach for top-corrected Gini coefficients where we impute top incomes in survey data using information on top income distribution from tax data. We apply our approach to European EU-SILC survey data which in some countries include administrative data. We find higher inequality in those European countries that exclusively rely (Germany, UK) or have relied (Spain) on interviews for the provision of EU-SILC survey data as compared to countries that use administrative data.
{"title":"An Integrated Approach for Top-Corrected Ginis","authors":"C. Bartels, M. Metzing","doi":"10.2139/ssrn.2923659","DOIUrl":"https://doi.org/10.2139/ssrn.2923659","url":null,"abstract":"Household survey data provide a rich information set on income, household context and demographic variables, but tend to under report incomes at the very top of the distribution. Administrative data like tax records offer more precise information on top incomes, but at the expense of household context details and incomes of non-filers at the bottom of the distribution. We combine the benefits of the two data sources and develop an integrated approach for top-corrected Gini coefficients where we impute top incomes in survey data using information on top income distribution from tax data. We apply our approach to European EU-SILC survey data which in some countries include administrative data. We find higher inequality in those European countries that exclusively rely (Germany, UK) or have relied (Spain) on interviews for the provision of EU-SILC survey data as compared to countries that use administrative data.","PeriodicalId":111949,"journal":{"name":"Econometric Modeling: Microeconometric Models of Household Behavior eJournal","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-02-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125006760","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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