Pub Date : 2023-01-01DOI: 10.2478/izajolp-2023-0003
Markus Gebauer
Abstract This study develops a search and matching model for labour markets with temporary and permanent contracts. It matches empirical patterns of higher matching rates and lower surplus for temporary workers and predicts an increase in separation taxes leads to a fall in the number of new permanent jobs, an increase in their wages, and stable separation rates because temporary workers shield permanent workers from adverse shocks. We find empirical support using a regional French policy experiment, the “Contrat de Transition Professionelle”, which increased separation taxes for recently hired permanent workers in firms with fewer than 1,000 workers.
摘要:本文建立了具有临时合同和永久合同的劳动力市场的搜索和匹配模型。它与临时工更高的匹配率和更低的盈余的经验模式相匹配，并预测离职税的增加会导致新的永久工作数量的下降，工资的增加，以及稳定的离职率，因为临时工保护永久工人免受不利冲击。我们通过法国的一项地区性政策实验——“职业转型契约”(Contrat de Transition Professionelle)——找到了实证支持。该实验增加了员工少于1000人的企业中新聘用的固定员工的离职税。
{"title":"Job Protection — It is Good to be an Insider","authors":"Markus Gebauer","doi":"10.2478/izajolp-2023-0003","DOIUrl":"https://doi.org/10.2478/izajolp-2023-0003","url":null,"abstract":"Abstract This study develops a search and matching model for labour markets with temporary and permanent contracts. It matches empirical patterns of higher matching rates and lower surplus for temporary workers and predicts an increase in separation taxes leads to a fall in the number of new permanent jobs, an increase in their wages, and stable separation rates because temporary workers shield permanent workers from adverse shocks. We find empirical support using a regional French policy experiment, the “Contrat de Transition Professionelle”, which increased separation taxes for recently hired permanent workers in firms with fewer than 1,000 workers.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135505480","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 : 2023-01-01DOI: 10.2478/izajolp-2023-0002
Elena Jarocinska, Anna Ruzik-Sierdzińska
Abstract This paper quantifies the effect of Poland's 1999 pension reform on the inequality of future pension benefits. The reform increases inequality, both in the upper and lower parts of the distribution. The estimates, based on the 2012 Polish Household Budget Survey, show that the Gini coefficient reaches 0.27 once the full effect of the reform has materialized. Had the pre-reform system continued unchanged, the Gini coefficient would not be >0.19. The increased inequality of pension benefits is the result of the system gradually moving from a more redistributive defined benefit pension system to a system in which benefits are strongly linked to earnings. We show to what extent minimum pension benefits mitigate the increase in inequality under different scenarios.
{"title":"The distributional effects of the pension system reform in Poland","authors":"Elena Jarocinska, Anna Ruzik-Sierdzińska","doi":"10.2478/izajolp-2023-0002","DOIUrl":"https://doi.org/10.2478/izajolp-2023-0002","url":null,"abstract":"Abstract This paper quantifies the effect of Poland's 1999 pension reform on the inequality of future pension benefits. The reform increases inequality, both in the upper and lower parts of the distribution. The estimates, based on the 2012 Polish Household Budget Survey, show that the Gini coefficient reaches 0.27 once the full effect of the reform has materialized. Had the pre-reform system continued unchanged, the Gini coefficient would not be >0.19. The increased inequality of pension benefits is the result of the system gradually moving from a more redistributive defined benefit pension system to a system in which benefits are strongly linked to earnings. We show to what extent minimum pension benefits mitigate the increase in inequality under different scenarios.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41659618","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 : 2023-01-01DOI: 10.2478/izajolp-2023-0001
António Afonso, J. Jalles, Zoe Venter
Abstract This paper presents and describes a new database of major minimum wage and collective bargaining (CB) shocks covering 26 advanced economies over the period 1970–2020. The main advantage of this dataset is the precise identification of the nature and date of major shocks, which is valuable in many empirical applications. Based on the dataset, we observe that major changes in minimum wages have been more frequent than in CB in the last decades, and the majority of these were implemented during the 1980s and 1990s. In our empirical application, we find that minimum wage policy reductions have a medium-run positive impact on labor productivity and they lead to a fall in the unemployment rate. CB policy liberalizations do not seem to affect either productivity or capital formation, but they have a clear medium-term effect on the labor market. Moreover, CB policy liberalizations are characterized by a greater sensitivity to the prevailing business cycle conditions at the time of the shock (vis-à-vis minimum wage reforms).
{"title":"Minimum wage and collective bargaining shocks: a narrative database for advanced economies","authors":"António Afonso, J. Jalles, Zoe Venter","doi":"10.2478/izajolp-2023-0001","DOIUrl":"https://doi.org/10.2478/izajolp-2023-0001","url":null,"abstract":"Abstract This paper presents and describes a new database of major minimum wage and collective bargaining (CB) shocks covering 26 advanced economies over the period 1970–2020. The main advantage of this dataset is the precise identification of the nature and date of major shocks, which is valuable in many empirical applications. Based on the dataset, we observe that major changes in minimum wages have been more frequent than in CB in the last decades, and the majority of these were implemented during the 1980s and 1990s. In our empirical application, we find that minimum wage policy reductions have a medium-run positive impact on labor productivity and they lead to a fall in the unemployment rate. CB policy liberalizations do not seem to affect either productivity or capital formation, but they have a clear medium-term effect on the labor market. Moreover, CB policy liberalizations are characterized by a greater sensitivity to the prevailing business cycle conditions at the time of the shock (vis-à-vis minimum wage reforms).","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43854919","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 : 2023-01-01DOI: 10.2478/izajolp-2023-0004
Rainer Eppel, Helmut Mahringer
Abstract Many European countries are facing the key challenge of integrating low-skilled jobless young people into the labor market. From 2018 to 2020, the Public Employment Service (PES) in Vienna tested a new model of intensified support (“case management”). The target group consisted of young unemployed persons with low formal qualifications who were drawing on social assistance. Based on the pilot project and a propensity matching approach, we show that the increase in staff significantly increased the intensity of the counseling. It led to an increase in job proposals and active labor market program participation, as well as sanctions in the form of benefit suspensions for failure to keep PES appointments. In line with the goal, more of the young people were encouraged to take part in training and further education instead of being quickly placed in an unskilled job. However, in the three-year follow-up period, the intensified counseling did not (yet) have a significant effect on the overall extent of integration into employment. Regarding post-unemployment job quality, we find no effects on wages at the start of a job.
{"title":"The effects of more intensive counseling for disadvantaged unemployed youth","authors":"Rainer Eppel, Helmut Mahringer","doi":"10.2478/izajolp-2023-0004","DOIUrl":"https://doi.org/10.2478/izajolp-2023-0004","url":null,"abstract":"Abstract Many European countries are facing the key challenge of integrating low-skilled jobless young people into the labor market. From 2018 to 2020, the Public Employment Service (PES) in Vienna tested a new model of intensified support (“case management”). The target group consisted of young unemployed persons with low formal qualifications who were drawing on social assistance. Based on the pilot project and a propensity matching approach, we show that the increase in staff significantly increased the intensity of the counseling. It led to an increase in job proposals and active labor market program participation, as well as sanctions in the form of benefit suspensions for failure to keep PES appointments. In line with the goal, more of the young people were encouraged to take part in training and further education instead of being quickly placed in an unskilled job. However, in the three-year follow-up period, the intensified counseling did not (yet) have a significant effect on the overall extent of integration into employment. Regarding post-unemployment job quality, we find no effects on wages at the start of a job.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135508870","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 : 2023-01-01DOI: 10.2478/izajolp-2023-0007
Maurizio Bussolo, Damien Capelle, Michael M. Lokshin, Iván Torre, Hernan Winkler
Abstract During the last quarter century, job tenure in Europe has shortened. Using data from Eurostat Labor Force Surveys of 29 countries from 1995 to 2020 and applying an age-period-cohort decomposition to analyze changes in tenure for specific birth cohorts, we show that tenure has shrunk for cohorts born in more recent years. To account for compositional changes within cohorts, we estimate the probability of holding jobs of different durations, conditional on individual and employment-related characteristics. The estimations demonstrate that, over time, the likelihood of having a medium- or long-term job decreased and holding a short-term job increased. We also find that stricter job protection legislation appears to decrease the probability of holding a short-term job, and higher trade openness and ICT-related technological change are correlated with an increase of that probability.
{"title":"Explaining the Evolution of Job Tenure in Europe, 1995–2020","authors":"Maurizio Bussolo, Damien Capelle, Michael M. Lokshin, Iván Torre, Hernan Winkler","doi":"10.2478/izajolp-2023-0007","DOIUrl":"https://doi.org/10.2478/izajolp-2023-0007","url":null,"abstract":"Abstract During the last quarter century, job tenure in Europe has shortened. Using data from Eurostat Labor Force Surveys of 29 countries from 1995 to 2020 and applying an age-period-cohort decomposition to analyze changes in tenure for specific birth cohorts, we show that tenure has shrunk for cohorts born in more recent years. To account for compositional changes within cohorts, we estimate the probability of holding jobs of different durations, conditional on individual and employment-related characteristics. The estimations demonstrate that, over time, the likelihood of having a medium- or long-term job decreased and holding a short-term job increased. We also find that stricter job protection legislation appears to decrease the probability of holding a short-term job, and higher trade openness and ICT-related technological change are correlated with an increase of that probability.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135508881","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 : 2022-01-01DOI: 10.2478/izajolp-2022-0006
Jieun Lee
Abstract This paper examines the effect of a new maximum work hour restriction introduced in South Korea in 2018 that limited maximum working hours from 68 h/week to 52 h/week. I use difference-in-differences analysis with continuous treatment measuring the prevalence of those working longer than 52 h/week prior to the policy change across industry-occupation-education groups. I find that the policy reduces work hours while increasing monthly earnings and hourly wages for male full-time workers. However, I find that the policy does not significantly affect total work hours, total employment, and total worker pay at the industry-occupation-education group level.
{"title":"Effects of a national work hours restriction in a high hours country","authors":"Jieun Lee","doi":"10.2478/izajolp-2022-0006","DOIUrl":"https://doi.org/10.2478/izajolp-2022-0006","url":null,"abstract":"Abstract This paper examines the effect of a new maximum work hour restriction introduced in South Korea in 2018 that limited maximum working hours from 68 h/week to 52 h/week. I use difference-in-differences analysis with continuous treatment measuring the prevalence of those working longer than 52 h/week prior to the policy change across industry-occupation-education groups. I find that the policy reduces work hours while increasing monthly earnings and hourly wages for male full-time workers. However, I find that the policy does not significantly affect total work hours, total employment, and total worker pay at the industry-occupation-education group level.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45611225","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 : 2022-01-01DOI: 10.2478/izajolp-2022-0008
S. Bhargava, A. Kerr
Abstract We use microlevel data from the India Human Development Survey to test our hypothesis that ownership of time-saving household appliances results in the following: an increase in employment rates for married women; an increase in school enrollment rates; and a decrease in employment rates for children. We address the concern of endogeneity of appliance ownership by instrumenting household ownership of time-saving appliances by two family-specific time-using household assets and (1) average ownership rate among single women living in the same primary sampling unit (for the adult female sample) or (2) average ownership among households with no children living in the same primary sampling unit (for the child sample). Our results suggest a decrease in married women's and children's employment when ownership of time-saving appliances increases. Disaggregating our measure of employment, we find that married women use time-saving appliances as a substitute for human capital and increase their probability of working in more productive employment outside of the household.
{"title":"The effect of time-saving household appliance ownership on outcomes for children and married women: evidence from India","authors":"S. Bhargava, A. Kerr","doi":"10.2478/izajolp-2022-0008","DOIUrl":"https://doi.org/10.2478/izajolp-2022-0008","url":null,"abstract":"Abstract We use microlevel data from the India Human Development Survey to test our hypothesis that ownership of time-saving household appliances results in the following: an increase in employment rates for married women; an increase in school enrollment rates; and a decrease in employment rates for children. We address the concern of endogeneity of appliance ownership by instrumenting household ownership of time-saving appliances by two family-specific time-using household assets and (1) average ownership rate among single women living in the same primary sampling unit (for the adult female sample) or (2) average ownership among households with no children living in the same primary sampling unit (for the child sample). Our results suggest a decrease in married women's and children's employment when ownership of time-saving appliances increases. Disaggregating our measure of employment, we find that married women use time-saving appliances as a substitute for human capital and increase their probability of working in more productive employment outside of the household.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"48531842","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 : 2022-01-01DOI: 10.2478/izajolp-2022-0002
E. Andriopoulou, A. Karakitsios
Abstract During the last decade, unemployment in Greece climbed up to 28%, almost quadrupling due to the economic crisis that hit Greece. In the present paper, we examine the determinants of the unemployment dynamics and the impact of the minimum wage on the probability of making a transition into and out of unemployment. We use micro-level data from the Greek Labour Force Survey (LFS) of the period 2004 to 2019 and control for several demographic factors, macro-economic conditions, regional differences, and changes in the statutory minimum wage. The results suggest that individual-level characteristics play an important role in making a transition into or out of unemployment. Changes in the real minimum wage are estimated to have either a statistically insignificant or a very small impact on unemployment entries and exits. Further, the impact of economy's growth rate follows the theoretical predictions as higher growth rates increase unemployment outflows and decrease inflows, while the regional differences are also important. Our findings persist even when we split the sample in three periods (pre-crisis, crisis, recovery). The results have important policy implications. Given that the disemployment effect of the minimum wage seems to be very limited in the Greek labor market, while the socioeconomic characteristics and regional characteristics play an important role, improving the skills of individuals through the educational system and reskilling or up-skilling programs while targeting specific regions may facilitate labor market mobility.
{"title":"Unemployment transitions and the role of minimum wage: From pre-crisis to crisis and recovery","authors":"E. Andriopoulou, A. Karakitsios","doi":"10.2478/izajolp-2022-0002","DOIUrl":"https://doi.org/10.2478/izajolp-2022-0002","url":null,"abstract":"Abstract During the last decade, unemployment in Greece climbed up to 28%, almost quadrupling due to the economic crisis that hit Greece. In the present paper, we examine the determinants of the unemployment dynamics and the impact of the minimum wage on the probability of making a transition into and out of unemployment. We use micro-level data from the Greek Labour Force Survey (LFS) of the period 2004 to 2019 and control for several demographic factors, macro-economic conditions, regional differences, and changes in the statutory minimum wage. The results suggest that individual-level characteristics play an important role in making a transition into or out of unemployment. Changes in the real minimum wage are estimated to have either a statistically insignificant or a very small impact on unemployment entries and exits. Further, the impact of economy's growth rate follows the theoretical predictions as higher growth rates increase unemployment outflows and decrease inflows, while the regional differences are also important. Our findings persist even when we split the sample in three periods (pre-crisis, crisis, recovery). The results have important policy implications. Given that the disemployment effect of the minimum wage seems to be very limited in the Greek labor market, while the socioeconomic characteristics and regional characteristics play an important role, improving the skills of individuals through the educational system and reskilling or up-skilling programs while targeting specific regions may facilitate labor market mobility.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42923191","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 : 2022-01-01DOI: 10.2478/izajolp-2022-0007
Marco Bertoni, G. Brunello
Abstract We use European Union Labour Force Survey data for the period 2005–2018 to investigate the cyclicality of training in Europe. Consistent with the view that firms use recessions as times to update skills, we find that training participation is moderately countercyclical for the employed. Within the not-employed group, this is true also for the unemployed, who are likely to be involved in public training programs during recessions, but not for the inactive, who may be affected by liquidity constraints.
{"title":"Training during recessions: recent European evidence","authors":"Marco Bertoni, G. Brunello","doi":"10.2478/izajolp-2022-0007","DOIUrl":"https://doi.org/10.2478/izajolp-2022-0007","url":null,"abstract":"Abstract We use European Union Labour Force Survey data for the period 2005–2018 to investigate the cyclicality of training in Europe. Consistent with the view that firms use recessions as times to update skills, we find that training participation is moderately countercyclical for the employed. Within the not-employed group, this is true also for the unemployed, who are likely to be involved in public training programs during recessions, but not for the inactive, who may be affected by liquidity constraints.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47429958","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 : 2022-01-01DOI: 10.2478/izajolp-2022-0009
Klaus Grünberger, Edlira Narazani, Stefano Filauro, Aron Kiss
Abstract This paper analyzes the effects of hypothetical MW (HMW) increases on social and fiscal outcomes in 21 European Union (EU) countries with a statutory national MW (NMW) based on a microsimulation approach using EUROMOD. The methodological challenges related to the use of available EU household survey data are described, along with the choices made to address these challenges. The paper assesses hypothetical scenarios in which countries with a statutory NMW increase their minimum wage (MW) to various reference values, set in relation to the gross national median and average wage. The model simulations suggest that MW increases can significantly reduce in-work poverty, wage inequality, and the gender pay gap, while generally improving the public budget balance. The implied wage increases for the beneficiaries are substantial, while the implied increases in the aggregate wage bill are generally modest. Extensions explore possible effects on employment and labor supply at the intensive margin.
{"title":"Social and fiscal impacts of statutory minimum wages in EU countries: a microsimulation analysis with EUROMOD","authors":"Klaus Grünberger, Edlira Narazani, Stefano Filauro, Aron Kiss","doi":"10.2478/izajolp-2022-0009","DOIUrl":"https://doi.org/10.2478/izajolp-2022-0009","url":null,"abstract":"Abstract This paper analyzes the effects of hypothetical MW (HMW) increases on social and fiscal outcomes in 21 European Union (EU) countries with a statutory national MW (NMW) based on a microsimulation approach using EUROMOD. The methodological challenges related to the use of available EU household survey data are described, along with the choices made to address these challenges. The paper assesses hypothetical scenarios in which countries with a statutory NMW increase their minimum wage (MW) to various reference values, set in relation to the gross national median and average wage. The model simulations suggest that MW increases can significantly reduce in-work poverty, wage inequality, and the gender pay gap, while generally improving the public budget balance. The implied wage increases for the beneficiaries are substantial, while the implied increases in the aggregate wage bill are generally modest. Extensions explore possible effects on employment and labor supply at the intensive margin.","PeriodicalId":45367,"journal":{"name":"IZA Journal of Labor Policy","volume":null,"pages":null},"PeriodicalIF":0.5,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42509744","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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