This research explores how different parental leave reforms in West Germany impacted on the time mothers and fathers in couples spent on child care. I investigate indirect effects through mothers' labor market return decisions more in detail than previous studies and also examine potential direct associations of reforms of the leave period and benefits with maternal and paternal care time. The analysis uses multilevel multiprocess models for 1299 couples with a first or second birth based on data from the German Socio-Economic Panel (1984-2009). I estimate simultaneously the timing and extent of mothers' labor market return, selection into childbearing, and maternal and paternal child care time over the years following a first or second birth. The findings suggest that the extensions of the maximum period of low-paid or unpaid leave between 1986 and 1992 and the introduction of shorter well-paid leave and two 'daddy months' in 2007 indirectly affected maternal and paternal child care through changes in mothers' work return decisions. Even after controlling for these indirect effects and fathers' take-up of leave, the parental leave extensions were directly associated with longer maternal care time on weekdays, whereas father involvement in child care increased after the 2007 reform.
{"title":"Parental Leave Policies and Child Care Time in Couples after Childbirth","authors":"Pia S. Schober","doi":"10.2139/ssrn.2020177","DOIUrl":"https://doi.org/10.2139/ssrn.2020177","url":null,"abstract":"This research explores how different parental leave reforms in West Germany impacted on the time mothers and fathers in couples spent on child care. I investigate indirect effects through mothers' labor market return decisions more in detail than previous studies and also examine potential direct associations of reforms of the leave period and benefits with maternal and paternal care time. The analysis uses multilevel multiprocess models for 1299 couples with a first or second birth based on data from the German Socio-Economic Panel (1984-2009). I estimate simultaneously the timing and extent of mothers' labor market return, selection into childbearing, and maternal and paternal child care time over the years following a first or second birth. The findings suggest that the extensions of the maximum period of low-paid or unpaid leave between 1986 and 1992 and the introduction of shorter well-paid leave and two 'daddy months' in 2007 indirectly affected maternal and paternal child care through changes in mothers' work return decisions. Even after controlling for these indirect effects and fathers' take-up of leave, the parental leave extensions were directly associated with longer maternal care time on weekdays, whereas father involvement in child care increased after the 2007 reform.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126412672","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 impact of family income on the results of the Unified State Examination (the USE) and university choice in Russia. We argue that, even under the USE, which was introduced instead of high school exit exams and university-specific entrance exams, entrants from wealthy households still have an advantage in terms of access to higher education, since income positively affects USE scores through the channel of a higher level of investment in pre-entry coaching. Moreover, richer households make more effective decisions about university. We have found positive and significant relationships between the level of income and USE results for high school graduates, with an equal achievement before coaching. We subsequently propose that students from the most affluent households do invest more in additional types of preparation (pre-entry courses and individual lessons with tutors), and those extra classes provide a higher return for children from this particular income group. Finally, we show that holding the result of the USE equal, students with good and fair marks from wealthy families are admitted to universities with higher average USE score than those from poorer families. As a result, we can observe that income status is a factor that significantly influences enrollment to university.
{"title":"University Admission In Russia: Do the Wealthier Benefit from Standardized Exams?","authors":"I. Prakhov, M. Yudkevich","doi":"10.2139/ssrn.2005108","DOIUrl":"https://doi.org/10.2139/ssrn.2005108","url":null,"abstract":"This paper examines the impact of family income on the results of the Unified State Examination (the USE) and university choice in Russia. We argue that, even under the USE, which was introduced instead of high school exit exams and university-specific entrance exams, entrants from wealthy households still have an advantage in terms of access to higher education, since income positively affects USE scores through the channel of a higher level of investment in pre-entry coaching. Moreover, richer households make more effective decisions about university. We have found positive and significant relationships between the level of income and USE results for high school graduates, with an equal achievement before coaching. We subsequently propose that students from the most affluent households do invest more in additional types of preparation (pre-entry courses and individual lessons with tutors), and those extra classes provide a higher return for children from this particular income group. Finally, we show that holding the result of the USE equal, students with good and fair marks from wealthy families are admitted to universities with higher average USE score than those from poorer families. As a result, we can observe that income status is a factor that significantly influences enrollment to university.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-02-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128687461","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}
Student loans increase educational opportunities for students from all backgrounds. They have also been criticized as imposing financial and psychological hardships. We employ the data from restricted-use National Surveys of Recent College Graduates to conduct an in-depth investigation of the relationship between student loans and post-graduation labor market outcomes. Graduates with loans have systematically lower earnings than graduates without loans. Decomposition estimations show that most of the earnings differential is due to factors related to the choice and performance in college and unobservables. Student borrowers could benefit from more information about net returns to higher quality education conditional on borrowing.
{"title":"Student Loans and Early Post-Graduation Earnings: Evidence from Decomposition Analysis","authors":"Serguey Braguinsky, Atsushi Ohyama","doi":"10.2139/ssrn.2000821","DOIUrl":"https://doi.org/10.2139/ssrn.2000821","url":null,"abstract":"Student loans increase educational opportunities for students from all backgrounds. They have also been criticized as imposing financial and psychological hardships. We employ the data from restricted-use National Surveys of Recent College Graduates to conduct an in-depth investigation of the relationship between student loans and post-graduation labor market outcomes. Graduates with loans have systematically lower earnings than graduates without loans. Decomposition estimations show that most of the earnings differential is due to factors related to the choice and performance in college and unobservables. Student borrowers could benefit from more information about net returns to higher quality education conditional on borrowing.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-02-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116593855","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 use new household level data to simultaneously test three competing hypothesis about the primary cause of mortgage default. I consider the potential interactions of individual unemployment spells, negative equity, and unsecured debt. Unlike past studies that were only able to control for regional unemployment rates, I find that the double trigger event of job loss and negative equity is crucial in determining default as has been widely hypothesized in the literature. In every specification considered, the interaction term between unemployment and negative equity is significant indicating that double trigger events are the culprit in generating persistent defaults as hypothesized by Foote, Gerardi, and Willen (2009). I find that a person who has negative equity and who is unemployed is 10% more likely to default than a person who has just negative equity. The negative equity alone only makes a person 1.45% more likely to default, a factor of 6 smaller than the interaction probability. Unsecured debt plays a tertiary role compared to negative equity and unemployment, and past modifications make someone 20% more likely to have defaulted at the survey date. Redefaults, which are defaults after modification, are also well predicted by an interaction between unemployment and negative equity, and modifications are best predicted by past negative equity which makes someone 8% more likely to receive a modification.
{"title":"What Actually Causes Mortgage Defaults, Redefaults, and Modifications","authors":"Kyle F. Herkenhoff","doi":"10.2139/ssrn.1997890","DOIUrl":"https://doi.org/10.2139/ssrn.1997890","url":null,"abstract":"I use new household level data to simultaneously test three competing hypothesis about the primary cause of mortgage default. I consider the potential interactions of individual unemployment spells, negative equity, and unsecured debt. Unlike past studies that were only able to control for regional unemployment rates, I find that the double trigger event of job loss and negative equity is crucial in determining default as has been widely hypothesized in the literature. In every specification considered, the interaction term between unemployment and negative equity is significant indicating that double trigger events are the culprit in generating persistent defaults as hypothesized by Foote, Gerardi, and Willen (2009). I find that a person who has negative equity and who is unemployed is 10% more likely to default than a person who has just negative equity. The negative equity alone only makes a person 1.45% more likely to default, a factor of 6 smaller than the interaction probability. Unsecured debt plays a tertiary role compared to negative equity and unemployment, and past modifications make someone 20% more likely to have defaulted at the survey date. Redefaults, which are defaults after modification, are also well predicted by an interaction between unemployment and negative equity, and modifications are best predicted by past negative equity which makes someone 8% more likely to receive a modification.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-02-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133205928","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 branding literature usually considers the brand as an independent variable comprised of a central construct with a variety of elements attached to it. This paper argues that more emphasis needs to be placed on the consumer perspective. However, research on the use of brands in the consumer decision making process is scant. The core objective of this study is to develop and test a multi item scale, the Brand Superiority Scale (BSP), which uses consumer’s use of brand names as guidance tools. The test results indicate that BSP has adequate internal reliability and a sound construct validity. Application of the scale in further consumer preference studies is reccommended.
{"title":"Development and Validation of the Brand Superiority Scale","authors":"Ilias Kapareliotis","doi":"10.2139/ssrn.1992899","DOIUrl":"https://doi.org/10.2139/ssrn.1992899","url":null,"abstract":"The branding literature usually considers the brand as an independent variable comprised of a central construct with a variety of elements attached to it. This paper argues that more emphasis needs to be placed on the consumer perspective. However, research on the use of brands in the consumer decision making process is scant. The core objective of this study is to develop and test a multi item scale, the Brand Superiority Scale (BSP), which uses consumer’s use of brand names as guidance tools. The test results indicate that BSP has adequate internal reliability and a sound construct validity. Application of the scale in further consumer preference studies is reccommended.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129125092","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 : 2012-01-27DOI: 10.1108/S1479-8387(2012)0000008014
Ruth V. Aguilera, Kurt A. Desender
This paper discusses the role that indices of corporate governance have had in comparative corporate governance research. To do so, we begin with a short discussion of what corporate governance is and its main debates. Then, we review the main indices (which are also summarized in Table 1) highlighting their strengths and limitations as well as describing some of the findings that emanate from them. In section 3, we discuss the methodological and conceptual assumptions of corporate governance indices which may compromise their construct validity. We conclude in section 4 with some encouraging suggestions for key methodological and research design issues to take into account in future comparative corporate governance.
{"title":"Challenges in the Measuring of Comparative Corporate Governance: A Review of the Main Indices","authors":"Ruth V. Aguilera, Kurt A. Desender","doi":"10.1108/S1479-8387(2012)0000008014","DOIUrl":"https://doi.org/10.1108/S1479-8387(2012)0000008014","url":null,"abstract":"This paper discusses the role that indices of corporate governance have had in comparative corporate governance research. To do so, we begin with a short discussion of what corporate governance is and its main debates. Then, we review the main indices (which are also summarized in Table 1) highlighting their strengths and limitations as well as describing some of the findings that emanate from them. In section 3, we discuss the methodological and conceptual assumptions of corporate governance indices which may compromise their construct validity. We conclude in section 4 with some encouraging suggestions for key methodological and research design issues to take into account in future comparative corporate governance.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-01-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114695287","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 study, I investigate whether managers’ capitalization of intangible expenditures conveys incremental information, about the amount and timing of future cash flows, to expensed intangible expenditures. I find the association between capitalized SD (Software Development) expenditures and future cash flows is stronger than the association between reported RD indicating managers may use the capitalization decision to convey private information when incentives to do so are higher. However, I find the association is lower for firms whose capitalized SD expenditures allows them to meet or beat analysts’ forecasts, consistent with managers using the capitalization decision opportunistically. These findings suggest that on average managers who capitalize SD expenditures use their private information to convey the future cash flow implications of SD expenditures; but that in some situations they may also use the capitalization decision opportunistically.
{"title":"The Capitalization of Intangibles and Managerial Information","authors":"Mindy Wolfe","doi":"10.2139/SSRN.1985664","DOIUrl":"https://doi.org/10.2139/SSRN.1985664","url":null,"abstract":"In this study, I investigate whether managers’ capitalization of intangible expenditures conveys incremental information, about the amount and timing of future cash flows, to expensed intangible expenditures. I find the association between capitalized SD (Software Development) expenditures and future cash flows is stronger than the association between reported RD indicating managers may use the capitalization decision to convey private information when incentives to do so are higher. However, I find the association is lower for firms whose capitalized SD expenditures allows them to meet or beat analysts’ forecasts, consistent with managers using the capitalization decision opportunistically. These findings suggest that on average managers who capitalize SD expenditures use their private information to convey the future cash flow implications of SD expenditures; but that in some situations they may also use the capitalization decision opportunistically.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-01-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114359049","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}
Rose & Spiegel (2011) find that Olympic Games host countries experience significant positive, lasting effects on exports. They interpret their results as an indication that countries use the hosting of such events to signal openness and competitiveness. We challenge these empirical findings on the grounds that a comparison of structurally different and non-matching groups of countries might suffer from a selection bias. We demonstrate that with an appropriate matching and treatment methodology, the significant Olympic effect disappears.
Rose & Spiegel(2011)发现，奥运会主办国对出口有显著的积极、持久的影响。他们将调查结果解释为，各国利用举办此类赛事来表明其开放性和竞争力。我们对这些实证发现提出质疑，理由是对结构不同和不匹配的国家群体进行比较可能会产生选择偏差。我们证明，通过适当的匹配和处理方法，显著的奥林匹克效应消失。
{"title":"Exports and Olympic Games: Is there a Signal Effect?","authors":"W. Maennig, F. Richter","doi":"10.2139/ssrn.1935345","DOIUrl":"https://doi.org/10.2139/ssrn.1935345","url":null,"abstract":"Rose & Spiegel (2011) find that Olympic Games host countries experience significant positive, lasting effects on exports. They interpret their results as an indication that countries use the hosting of such events to signal openness and competitiveness. We challenge these empirical findings on the grounds that a comparison of structurally different and non-matching groups of countries might suffer from a selection bias. We demonstrate that with an appropriate matching and treatment methodology, the significant Olympic effect disappears.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129584551","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 : 2012-01-01DOI: 10.1111/j.1467-9930.2011.00353.x
Lorraine Mazerolle, Gentry White, Janet Ransley, Patricia L. Ferguson
Violence in entertainment districts is a major problem across urban landscapes throughout the world. Research shows that licensed premises are the third most common location for homicides and serious assaults, accounting for one in ten fatal and nonfatal assaults. One class of interventions that aims to reduce violence in entertainment districts involves the use of civil remedies: a group of strategies that use civil or regulatory measures as legal “levers” to reduce problem behavior. One specific civil remedy used to reduce problematic behavior in entertainment districts involves manipulation of licensed premise trading hours. This article uses generalized linear models to analyze the impact of lockout legislation on recorded violent offences in two entertainment districts in the Australian state of Queensland. Our research shows that 3 a.m. lockout legislation led to a direct and significant reduction in the number of violent incidents inside licensed premises. Indeed, the lockouts cut the level of violent crime inside licensed premises by half. Despite these impressive results for the control of violence inside licensed premises, we found no evidence that the lockout had any impact on violence on streets and footpaths outside licensed premises that were the site for more than 80 percent of entertainment district violence. Overall, however, our analysis suggests that lockouts are an important mechanism that helps to control the level of violence inside licensed premises but that finely grained contextual responses to alcohol-related problems are needed rather than one-size-fits-all solutions.
{"title":"Violence in and Around Entertainment Districts: A Longitudinal Analysis of the Impact of Late‐Night Lockout Legislation","authors":"Lorraine Mazerolle, Gentry White, Janet Ransley, Patricia L. Ferguson","doi":"10.1111/j.1467-9930.2011.00353.x","DOIUrl":"https://doi.org/10.1111/j.1467-9930.2011.00353.x","url":null,"abstract":"Violence in entertainment districts is a major problem across urban landscapes throughout the world. Research shows that licensed premises are the third most common location for homicides and serious assaults, accounting for one in ten fatal and nonfatal assaults. One class of interventions that aims to reduce violence in entertainment districts involves the use of civil remedies: a group of strategies that use civil or regulatory measures as legal “levers” to reduce problem behavior. One specific civil remedy used to reduce problematic behavior in entertainment districts involves manipulation of licensed premise trading hours. This article uses generalized linear models to analyze the impact of lockout legislation on recorded violent offences in two entertainment districts in the Australian state of Queensland. Our research shows that 3 a.m. lockout legislation led to a direct and significant reduction in the number of violent incidents inside licensed premises. Indeed, the lockouts cut the level of violent crime inside licensed premises by half. Despite these impressive results for the control of violence inside licensed premises, we found no evidence that the lockout had any impact on violence on streets and footpaths outside licensed premises that were the site for more than 80 percent of entertainment district violence. Overall, however, our analysis suggests that lockouts are an important mechanism that helps to control the level of violence inside licensed premises but that finely grained contextual responses to alcohol-related problems are needed rather than one-size-fits-all solutions.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117878174","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 use Data Envelopment Analysis (DEA) to estimate how well China’s urban areas absorb migrant workers under the interaction of urbanization and industrialization. We applied an output-oriented BCC model to evaluate provincial and regional rural labor absorption efficiency in mainland China. It appears that 4 out of 31 provinces and municipals are efficient, and 2 out of 8 economic regions are efficient in absorbing migrant workers. In the southern and eastern parts of China, urban labor absorption efficiency is higher compared with the western and northern parts of China. Different urbanization patterns and industrial development strategies should be adopted in different economic areas to enhance labor absorption ability in these areas. Urban areas in many parts of China still have potential to accommodate rural migrant workers. The inter-regional flow of production factors would affect urban labor absorption efficiency.
{"title":"Rural Labor Absorption Efficiency in Urban Areas Under Different Urbanization Patterns and Industrial Structures: The Case of China","authors":"Chen Li-wen, Xiangquan. Zeng, Yong Yumei","doi":"10.2139/ssrn.1976520","DOIUrl":"https://doi.org/10.2139/ssrn.1976520","url":null,"abstract":"In this paper, we use Data Envelopment Analysis (DEA) to estimate how well China’s urban areas absorb migrant workers under the interaction of urbanization and industrialization. We applied an output-oriented BCC model to evaluate provincial and regional rural labor absorption efficiency in mainland China. It appears that 4 out of 31 provinces and municipals are efficient, and 2 out of 8 economic regions are efficient in absorbing migrant workers. In the southern and eastern parts of China, urban labor absorption efficiency is higher compared with the western and northern parts of China. Different urbanization patterns and industrial development strategies should be adopted in different economic areas to enhance labor absorption ability in these areas. Urban areas in many parts of China still have potential to accommodate rural migrant workers. The inter-regional flow of production factors would affect urban labor absorption efficiency.","PeriodicalId":306816,"journal":{"name":"Econometrics: Applied Econometric Modeling in Microeconomics eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2011-12-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128454040","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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