Prc Working Papers, Nathan Fabian, Mikael Homanen, Nikolaj Pedersen, Morgan Slebos
Retirement system sustainability is defined as the ability of plan boards and managers to be responsible investors, active stewards, and allocators of capital to economic activities with desirable social and environmental outcomes. In this paper, we examine the policy frameworks and important structural variables pertinent to private retirement systems in Australia, the UK, and the US. By analyzing various reports, interviewing experts, and using data from the Principles of Responsible Investment as well as national pension and retirement authorities, we identify key structural challenges within national retirement systems. These include market fragmentation, principal-agent conflicts in personal pensions, and the role of service providers. Our results provide insight into how, or whether, retirement systems can facilitate desirable economic, social, and environmental outcomes.
{"title":"Private Retirement Systems and Sustainability: Insights from Australia, the UK, and the US","authors":"Prc Working Papers, Nathan Fabian, Mikael Homanen, Nikolaj Pedersen, Morgan Slebos","doi":"10.2139/ssrn.3885848","DOIUrl":"https://doi.org/10.2139/ssrn.3885848","url":null,"abstract":"Retirement system sustainability is defined as the ability of plan boards and managers to be responsible investors, active stewards, and allocators of capital to economic activities with desirable social and environmental outcomes. In this paper, we examine the policy frameworks and important structural variables pertinent to private retirement systems in Australia, the UK, and the US. By analyzing various reports, interviewing experts, and using data from the Principles of Responsible Investment as well as national pension and retirement authorities, we identify key structural challenges within national retirement systems. These include market fragmentation, principal-agent conflicts in personal pensions, and the role of service providers. Our results provide insight into how, or whether, retirement systems can facilitate desirable economic, social, and environmental outcomes.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129708062","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}
Elisa Guglielminetti, M. Loberto, G. Zevi, R. Zizza
We quantify the impact of the Covid-19 pandemic on housing demand of Italian households by exploiting new information on their search activity on the market. The data comes from two unique datasets: the Italian Housing Market Survey, conducted quarterly on a large sample of real estate agents, and the universe of weekly housing sales advertisements taken from Immobiliare.it, a popular online portal for real estate services in Italy. The latter includes high-frequency and house-specific measures of online interest of potential home buyers. The pandemic induced a large increase in demand for houses located in areas with lower population density, mainly driven by a significant shift in preferences towards larger, single-family housing units, endowed with outdoor spaces. Fear of contagion, lockdown measures and the rise of remote working arrangements all likely shaped the evolution of housing demand, with potential long-lasting consequences on the housing market.
{"title":"Living on my Own: The Impact of the Covid-19 Pandemic on Housing Preferences","authors":"Elisa Guglielminetti, M. Loberto, G. Zevi, R. Zizza","doi":"10.2139/ssrn.3891671","DOIUrl":"https://doi.org/10.2139/ssrn.3891671","url":null,"abstract":"We quantify the impact of the Covid-19 pandemic on housing demand of Italian households by exploiting new information on their search activity on the market. The data comes from two unique datasets: the Italian Housing Market Survey, conducted quarterly on a large sample of real estate agents, and the universe of weekly housing sales advertisements taken from Immobiliare.it, a popular online portal for real estate services in Italy. The latter includes high-frequency and house-specific measures of online interest of potential home buyers. The pandemic induced a large increase in demand for houses located in areas with lower population density, mainly driven by a significant shift in preferences towards larger, single-family housing units, endowed with outdoor spaces. Fear of contagion, lockdown measures and the rise of remote working arrangements all likely shaped the evolution of housing demand, with potential long-lasting consequences on the housing market.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"115 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124246520","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 study investigates the effect of debt adjustment for bad debts on debt repayment and discusses the optimal principal reduction rate. We use a logit model and propensity score matching, employing the unique dataset of creditors’ ledger, debt adjustment information, and debtors’ characteristics from KR&C, which manages bad debts in Korea. Classifying debtors into beneficiaries and non-beneficiaries of the debt adjustment program, we find that the repayment amounts of beneficiaries are larger than those of non-beneficiaries. Additionally, a quadratic function consisting of expected repayment rates and reduction rates is postulated to explore the moral hazards that may arise if the principal reduction rate is expanded, and an appropriate reduction rate is derived. We find that if the reduction rate is expanded from 60% to 70%, it does not reach the maximum repayment rate, but the effectiveness of the debt adjustment system and the stability of the fund are maintained.
{"title":"The Effect of Bad Debt Adjustment on Repayment: Evidence From KR&C’s Dataset in South Korea","authors":"Namhyun Kim, Sanha Noh","doi":"10.2139/ssrn.3874515","DOIUrl":"https://doi.org/10.2139/ssrn.3874515","url":null,"abstract":"This study investigates the effect of debt adjustment for bad debts on debt repayment and discusses the optimal principal reduction rate. We use a logit model and propensity score matching, employing the unique dataset of creditors’ ledger, debt adjustment information, and debtors’ characteristics from KR&C, which manages bad debts in Korea. Classifying debtors into beneficiaries and non-beneficiaries of the debt adjustment program, we find that the repayment amounts of beneficiaries are larger than those of non-beneficiaries. Additionally, a quadratic function consisting of expected repayment rates and reduction rates is postulated to explore the moral hazards that may arise if the principal reduction rate is expanded, and an appropriate reduction rate is derived. We find that if the reduction rate is expanded from 60% to 70%, it does not reach the maximum repayment rate, but the effectiveness of the debt adjustment system and the stability of the fund are maintained.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"180 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123133190","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}
Why is wealth so concentrated in the United States? In this paper, I investigate the role of return heterogeneity as a source of wealth inequality. Using household-level data from the Survey of Consumer Finances (1989-2019), I provide new empirical evidence on returns to wealth in the United States, and find that wealthier households earn, on average, higher returns: moving from the 20th to the 99th percentile of the wealth distribution raises the average yearly return from 3.6% to 8.3%. To understand how these return differences shape the distribution of wealth, I introduce realistic return heterogeneity in a partial equilibrium model of household saving behavior. This exercise suggests that considering both earnings and return heterogeneity can fully account for the top 10% wealth share observed in the data (76%), which cannot be explained by earnings differences alone.
{"title":"Wealth Inequality in the US: the Role of Heterogeneous Returns","authors":"I. Xavier","doi":"10.2139/ssrn.3915439","DOIUrl":"https://doi.org/10.2139/ssrn.3915439","url":null,"abstract":"Why is wealth so concentrated in the United States? In this paper, I investigate the role of return heterogeneity as a source of wealth inequality. Using household-level data from the Survey of Consumer Finances (1989-2019), I provide new empirical evidence on returns to wealth in the United States, and find that wealthier households earn, on average, higher returns: moving from the 20th to the 99th percentile of the wealth distribution raises the average yearly return from 3.6% to 8.3%. To understand how these return differences shape the distribution of wealth, I introduce realistic return heterogeneity in a partial equilibrium model of household saving behavior. This exercise suggests that considering both earnings and return heterogeneity can fully account for the top 10% wealth share observed in the data (76%), which cannot be explained by earnings differences alone.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"33 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124791549","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}
We analyze the portfolio choices of approximately 913,000 active participants in employee saving plans in France. Looking at the cross-section of equity exposure, we find that the inclusion of responsible equity options in the menu of available funds is associated with a 2.1% higher equity allocation by plan participants. Compared to an average equity asset allocation of 12.1%, it represents a material increase (17% in relative terms). Difference-in-differences analyses confirm that the introduction of a responsible equity option to a saving plan is followed by an increase of 7.2% in participants' appetite for stocks, contrary to what happens with conventional equity funds.
{"title":"Responsible Investing and Stock Allocation","authors":"M. Brière, Stefano Ramelli","doi":"10.2139/ssrn.3853256","DOIUrl":"https://doi.org/10.2139/ssrn.3853256","url":null,"abstract":"We analyze the portfolio choices of approximately 913,000 active participants in<br>employee saving plans in France. Looking at the cross-section of equity exposure, we<br>find that the inclusion of responsible equity options in the menu of available funds<br>is associated with a 2.1% higher equity allocation by plan participants. Compared<br>to an average equity asset allocation of 12.1%, it represents a material increase (17%<br>in relative terms). Difference-in-differences analyses confirm that the introduction<br>of a responsible equity option to a saving plan is followed by an increase of 7.2% in<br>participants' appetite for stocks, contrary to what happens with conventional equity<br>funds.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121836997","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}
Kaplan Sanders, Olamide Olajide, Michael Guillemette
A great deal of research has studied the use of margin from an overall market perspective. However, very little has been observed regarding household decisions around margin use. The 2018 wave of the National Financial Capability Study Investor Survey provides unique insight into household margin use, and these new variables have made studying margin use on a household level possible. This study investigates the relation between both objective and subjective investment literacy, as well as the divergence in investment literacy and margin use. Results indicate that respondents who have a higher level of subjective investment literacy than objective investment literacy (investors who think they know more than they actually do) have a higher probability of buying on margin. This finding appears to be even more pronounced for respondents who receive investment advice from brokers compared to those who do not.
{"title":"A Household View of Making Purchases on Margin: Focusing on Divergence in Investment Literacy and Advice Seeking Behavior","authors":"Kaplan Sanders, Olamide Olajide, Michael Guillemette","doi":"10.2139/ssrn.3849589","DOIUrl":"https://doi.org/10.2139/ssrn.3849589","url":null,"abstract":"A great deal of research has studied the use of margin from an overall market perspective. However, very little has been observed regarding household decisions around margin use. The 2018 wave of the National Financial Capability Study Investor Survey provides unique insight into household margin use, and these new variables have made studying margin use on a household level possible. This study investigates the relation between both objective and subjective investment literacy, as well as the divergence in investment literacy and margin use. Results indicate that respondents who have a higher level of subjective investment literacy than objective investment literacy (investors who think they know more than they actually do) have a higher probability of buying on margin. This finding appears to be even more pronounced for respondents who receive investment advice from brokers compared to those who do not.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129339809","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}
Michael S. Barr, A. Harris, Lev Menand, Karin Thrasher
This brief is part of the Central Bank of the Future Project (“CBOTF”), a research project that seeks to identify ways that central banks across the world can improve access to financial products and services for underserved communities. CBOTF engages with scholars, financial regulators and policymakers, think tanks, financial institutions, fintech companies, consumer and community organizations, and other stakeholders to examine how central banks can evolve to better promote financial inclusion and financial health. CBOTF also works to find ways that businesses and nonprofits can work alongside government sector efforts for financial inclusion. One output is a series of working papers and policy briefs focused on specific topics.
This paper examines how central banks might use distributed ledger technology (“DLT”) to improve access to safe and affordable financial products and services. We consider how central banks might use DLT to advance objectives such as Anti-Money Laundering (“AML”) compliance and discuss both central bank digital currencies (“CBDC”) and private digital currencies. We consider implementation challenges for these new approaches relating to interoperability, privacy, and efficiency. We conclude that financial inclusion is far from an assured outcome: central banks must work to ensure that any new technologies they adopt or foster do not exclude marginalized groups and instead focus with intentionality on low-income households. Moreover, difficult issues with respect to financial disintermediation, credit availability, and financial stability would need to be addressed.
This paper proceeds in four parts. Part II provides a primer on DLT and CBDC. Part III considers four ways central banks might use DLT to advance financial inclusion: to accelerate payments, to improve identity verification, to formalize collateral, and to lower compliance costs. Part IV focuses on DLT in the digital currency context, analyzing non-fiat DLT-based digital currencies and proposals to create DLT and non-DLT central bank digital currencies. Part V concludes.
{"title":"Should Central Banks Use Distributed Ledger Technology and Digital Currencies to Advance Financial Inclusion?","authors":"Michael S. Barr, A. Harris, Lev Menand, Karin Thrasher","doi":"10.2139/ssrn.3849051","DOIUrl":"https://doi.org/10.2139/ssrn.3849051","url":null,"abstract":"This brief is part of the Central Bank of the Future Project (“CBOTF”), a research project that seeks to identify ways that central banks across the world can improve access to financial products and services for underserved communities. CBOTF engages with scholars, financial regulators and policymakers, think tanks, financial institutions, fintech companies, consumer and community organizations, and other stakeholders to examine how central banks can evolve to better promote financial inclusion and financial health. CBOTF also works to find ways that businesses and nonprofits can work alongside government sector efforts for financial inclusion. One output is a series of working papers and policy briefs focused on specific topics. <br><br>This paper examines how central banks might use distributed ledger technology (“DLT”) to improve access to safe and affordable financial products and services. We consider how central banks might use DLT to advance objectives such as Anti-Money Laundering (“AML”) compliance and discuss both central bank digital currencies (“CBDC”) and private digital currencies. We consider implementation challenges for these new approaches relating to interoperability, privacy, and efficiency. We conclude that financial inclusion is far from an assured outcome: central banks must work to ensure that any new technologies they adopt or foster do not exclude marginalized groups and instead focus with intentionality on low-income households. Moreover, difficult issues with respect to financial disintermediation, credit availability, and financial stability would need to be addressed. <br><br>This paper proceeds in four parts. Part II provides a primer on DLT and CBDC. Part III considers four ways central banks might use DLT to advance financial inclusion: to accelerate payments, to improve identity verification, to formalize collateral, and to lower compliance costs. Part IV focuses on DLT in the digital currency context, analyzing non-fiat DLT-based digital currencies and proposals to create DLT and non-DLT central bank digital currencies. Part V concludes.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133801507","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}
We identify the existence of a racial gap in housing returns that is an order of magnitude larger than disparities arising from housing costs alone. The returns gap is driven almost entirely by differences in distressed home sales (i.e. foreclosures and short sales). Black and Hispanic homeowners are both more likely to experience a distressed sale and to live in neighborhoods where distressed sales carry larger foreclosure discounts. Higher rates of distressed sales among minorities are driven by pre-existing differences in economic stability and neighborhood sorting. Black and Hispanic homeowners are more likely to default in response to increases in monthly payments, consistent with racial differences in liquid wealth holdings playing a key role in creating the observed disparities. We use quasi-experimental variation in the receipt of mortgage modifications to show that policies that encourage lenders to modify loans when homeowners can no longer afford their mortgages can mitigate gaps in housing returns, particularly if they are targeted towards minority homeowners or neighborhoods.
{"title":"Racial Disparities in Housing Returns","authors":"A. Kermani, Francis Wong","doi":"10.2139/ssrn.3846569","DOIUrl":"https://doi.org/10.2139/ssrn.3846569","url":null,"abstract":"We identify the existence of a racial gap in housing returns that is an order of magnitude larger than disparities arising from housing costs alone. The returns gap is driven almost entirely by differences in distressed home sales (i.e. foreclosures and short sales). Black and Hispanic homeowners are both more likely to experience a distressed sale and to live in neighborhoods where distressed sales carry larger foreclosure discounts. Higher rates of distressed sales among minorities are driven by pre-existing differences in economic stability and neighborhood sorting. Black and Hispanic homeowners are more likely to default in response to increases in monthly payments, consistent with racial differences in liquid wealth holdings playing a key role in creating the observed disparities. We use quasi-experimental variation in the receipt of mortgage modifications to show that policies that encourage lenders to modify loans when homeowners can no longer afford their mortgages can mitigate gaps in housing returns, particularly if they are targeted towards minority homeowners or neighborhoods.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"164 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132101832","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 takes up the much argued-over term "middle class" and specifically the standard of consumption the term may be said to denote. In the history this paper recounts it notes the ambiguities and evolution of the term, but holds that in the post-World War II United States it denoted a certain minimum standard of comfort, security and opportunity for one's children (home and car ownership, health insurance, college for the children, retirement, and a margin of safety and resources for superfluities on a single income). The paper also argues, on the basis of the cost of the requisite amenities, the actual distribution of income and other evidence that far from being some broad societal norm all this is actually accessible only to a few, a fact which may be finding some reflection in the country's shifting politics.
{"title":"'What Qualifies a Household's Living Standard as Middle Class?' A Note","authors":"N. Elhefnawy","doi":"10.2139/ssrn.3860761","DOIUrl":"https://doi.org/10.2139/ssrn.3860761","url":null,"abstract":"This paper takes up the much argued-over term \"middle class\" and specifically the standard of consumption the term may be said to denote. In the history this paper recounts it notes the ambiguities and evolution of the term, but holds that in the post-World War II United States it denoted a certain minimum standard of comfort, security and opportunity for one's children (home and car ownership, health insurance, college for the children, retirement, and a margin of safety and resources for superfluities on a single income). The paper also argues, on the basis of the cost of the requisite amenities, the actual distribution of income and other evidence that far from being some broad societal norm all this is actually accessible only to a few, a fact which may be finding some reflection in the country's shifting politics.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-05-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125257379","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}
Constantinos Antoniou, C. Firth, David Leake, Neil Stewart
We ask to what extent task knowledge and tactics, or enduring personality traits, predict behaviour and biases in a stock trading setting. We base our study on an exceptionally wide-ranging dataset: responses to a self-report survey, together with transactional data of the same individual customers of a UK brokerage. From the survey we estimate measures of domain-general personality traits, such as the Big Five, and task-related measures of financial literacy, competency and attitude specific to trading. Our results show the dominance of task measures over trait measures, when predicting nine different dependent variables of investment performance, biases and portfolio activity. We argue that researchers into financial decisions should consider a rich set of explanatory factors.
{"title":"Behaviour and Biases of Retail Investors: Task or Trait?","authors":"Constantinos Antoniou, C. Firth, David Leake, Neil Stewart","doi":"10.2139/ssrn.3791634","DOIUrl":"https://doi.org/10.2139/ssrn.3791634","url":null,"abstract":"We ask to what extent task knowledge and tactics, or enduring personality traits, predict behaviour and biases in a stock trading setting. We base our study on an exceptionally wide-ranging dataset: responses to a self-report survey, together with transactional data of the same individual customers of a UK brokerage. From the survey we estimate measures of domain-general personality traits, such as the Big Five, and task-related measures of financial literacy, competency and attitude specific to trading. Our results show the dominance of task measures over trait measures, when predicting nine different dependent variables of investment performance, biases and portfolio activity. We argue that researchers into financial decisions should consider a rich set of explanatory factors.","PeriodicalId":428959,"journal":{"name":"Household Finance eJournal","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128331701","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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