This paper provides a non-technical summary of two recent empirical studies to shed light on key important issues regarding the implementation of loan-to-value (LTV) policy as a macroprudential tool, including its effectiveness, potential drawbacks and its transmission mechanism to improve financial stability. Empirical evidence suggests that LTV policy is effective in reducing systemic risk associated with boom-and-bust cycles in property markets. Although the LTV policy may be associated with higher liquidity constraints on homebuyers, we show that the mortgage insurance program (MIP) can mitigate this drawback without undermining the effectiveness of LTV policy. Thus, MIPs play an important role in enhancing the net benefits of LTV policy. Concerning the transmission mechanism, empirical evidence suggests that the policy pass-through to property market activities may be weak. By contrast, there is clear evidence that tightening the LTV cap would reduce household leverage and credit growth, and that lower leverage plays a major role in strengthening banks’ resilience to property price shocks. This finding supports the view that household leverage would be an optimal target of LTV policy.
{"title":"Effectiveness of Loan-to-Value Ratio Policy and Its Transmission Mechanism – Empirical Evidence from Hong Kong","authors":"T. Wong, Kelvin Ho, Andrew Tsang","doi":"10.2139/ssrn.2685559","DOIUrl":"https://doi.org/10.2139/ssrn.2685559","url":null,"abstract":"This paper provides a non-technical summary of two recent empirical studies to shed light on key important issues regarding the implementation of loan-to-value (LTV) policy as a macroprudential tool, including its effectiveness, potential drawbacks and its transmission mechanism to improve financial stability. Empirical evidence suggests that LTV policy is effective in reducing systemic risk associated with boom-and-bust cycles in property markets. Although the LTV policy may be associated with higher liquidity constraints on homebuyers, we show that the mortgage insurance program (MIP) can mitigate this drawback without undermining the effectiveness of LTV policy. Thus, MIPs play an important role in enhancing the net benefits of LTV policy. Concerning the transmission mechanism, empirical evidence suggests that the policy pass-through to property market activities may be weak. By contrast, there is clear evidence that tightening the LTV cap would reduce household leverage and credit growth, and that lower leverage plays a major role in strengthening banks’ resilience to property price shocks. This finding supports the view that household leverage would be an optimal target of LTV policy.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78322060","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 analyzes the importance of financial constraints on the home ownership decision of European households and their differential effect in periods of positive expectations of housing prices. We document that financial constraints are key drivers of the household homeownership decision being wealth constraints more relevant than income constraints. The wealth constraint is less binding under a scenario in which housing prices exhibit an upward trend.
{"title":"Borrowing Constraints and Housing Price Expectations in the Euro Area","authors":"Miguel Ampudia, S. Mayordomo","doi":"10.2139/ssrn.2657176","DOIUrl":"https://doi.org/10.2139/ssrn.2657176","url":null,"abstract":"This paper analyzes the importance of financial constraints on the home ownership decision of European households and their differential effect in periods of positive expectations of housing prices. We document that financial constraints are key drivers of the household homeownership decision being wealth constraints more relevant than income constraints. The wealth constraint is less binding under a scenario in which housing prices exhibit an upward trend.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"11 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81622860","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}
Jordan Rappaport analyzes the forces driving the recent rebound in multifamily construction.
Jordan Rappaport分析了推动近期多户住宅建设反弹的力量。
{"title":"Millennials, Baby Boomers, and Rebounding Multifamily Home Construction","authors":"J. Rappaport","doi":"10.2139/ssrn.2637622","DOIUrl":"https://doi.org/10.2139/ssrn.2637622","url":null,"abstract":"Jordan Rappaport analyzes the forces driving the recent rebound in multifamily construction.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"143 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-06-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78203107","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 consider the effect of marketing expertise on economic transactions, with a particular focus on the real estate market. We show that even as listing information becomes increasingly accessible on real estate aggregation websites, realtor expertise remains important in securing a desirable sale price. One main channel for the effects of such expertise is improving information dissemination to potential buyers through higher quality listings. Using listing photos and remarks as measures of quality, we find that realtor activity is correlated with significantly higher quality listings. We then measure the price impact of these measures of quality and find that, even after controlling for a large spectrum of house characteristics, listing quality is correlated with higher sale prices.
{"title":"Marketing and Product Description: Value Added in the Real Estate Market","authors":"S. Gay, Allen Zhang","doi":"10.2139/ssrn.2690221","DOIUrl":"https://doi.org/10.2139/ssrn.2690221","url":null,"abstract":"We consider the effect of marketing expertise on economic transactions, with a particular focus on the real estate market. We show that even as listing information becomes increasingly accessible on real estate aggregation websites, realtor expertise remains important in securing a desirable sale price. One main channel for the effects of such expertise is improving information dissemination to potential buyers through higher quality listings. Using listing photos and remarks as measures of quality, we find that realtor activity is correlated with significantly higher quality listings. We then measure the price impact of these measures of quality and find that, even after controlling for a large spectrum of house characteristics, listing quality is correlated with higher sale prices.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"23 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86258373","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 issues of most importance to Latinos, according to a recent poll, are the economy/job creation, immigration reform, and education reform. Education reform is of particular importance because of the close correlation between educational achievement of individuals and greater employment and income prospects for them.Many people may believe that high high-school dropout rates for young people are due to the fact they live in cities with a relatively heavy concentration of Latinos. But this would be a mistake. It is not ethnicity or race that is the driving force in explaining differences in dropout rates in cities throughout the country.
{"title":"Housing Price Collapse Worsens the Opportunities for Educational Attainment for the Young in Cities Nationwide","authors":"I-Ling Shen, James R. Barth","doi":"10.2139/ssrn.2615950","DOIUrl":"https://doi.org/10.2139/ssrn.2615950","url":null,"abstract":"The issues of most importance to Latinos, according to a recent poll, are the economy/job creation, immigration reform, and education reform. Education reform is of particular importance because of the close correlation between educational achievement of individuals and greater employment and income prospects for them.Many people may believe that high high-school dropout rates for young people are due to the fact they live in cities with a relatively heavy concentration of Latinos. But this would be a mistake. It is not ethnicity or race that is the driving force in explaining differences in dropout rates in cities throughout the country.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"20 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-06-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86158759","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 United States is aging, and many baby boomers are reaching or will soon reach theretirement age of sixty-five. On the other hand, the Millennials, the largest generation in the U.S.history, has faced the problems of high rents relative to incomes and volatility in housing market.Given the shifts, we are again seeing growing debates about how these changes in age structurewill affect housing and labor markets.To address these concerns, we revisit Green and Hendershott (1996) and analyze the linksbetween the willingness to pay for a constant-quality house and demographics using the Census2000 and 2005-2011 American Community Survey 1-Year Public Use Microdata Sample data.The results generally reconfirm what Green and Hendershott (1996) found: The massivedemographic shift will not result in another housing crisis. This is because the educational andincome levels of the current and future seniors are relatively higher than before, leading them toconsume more than previous generations. Also, the size of the Millennial generation will drivethe growth of aggregate housing demand, although the growth of per household housing demandmay be relatively modest.
{"title":"Age, Demographics, and the Demand for Housing, Revisited","authors":"Richard K. Green, Hyojung Lee","doi":"10.2139/ssrn.2614638","DOIUrl":"https://doi.org/10.2139/ssrn.2614638","url":null,"abstract":"The United States is aging, and many baby boomers are reaching or will soon reach theretirement age of sixty-five. On the other hand, the Millennials, the largest generation in the U.S.history, has faced the problems of high rents relative to incomes and volatility in housing market.Given the shifts, we are again seeing growing debates about how these changes in age structurewill affect housing and labor markets.To address these concerns, we revisit Green and Hendershott (1996) and analyze the linksbetween the willingness to pay for a constant-quality house and demographics using the Census2000 and 2005-2011 American Community Survey 1-Year Public Use Microdata Sample data.The results generally reconfirm what Green and Hendershott (1996) found: The massivedemographic shift will not result in another housing crisis. This is because the educational andincome levels of the current and future seniors are relatively higher than before, leading them toconsume more than previous generations. Also, the size of the Millennial generation will drivethe growth of aggregate housing demand, although the growth of per household housing demandmay be relatively modest.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"2 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-06-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89058336","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}
Spanish Abstract: El presente estudio analiza la evolucion de los precios del mercado de vivienda ecuatoriano de manera agregada, a partir de datos de fuentes secundarias, en el periodo enero 2008-octubre 2014. Se aplico el Price to Earnings Ratio (PER), utilizado en el analisis bursatil para valorar comparativamente las acciones, pero adaptado al mercado de vivienda como la relacion Precio/Alquiler. El PER mostro que los precios de la vivienda han crecido a mayor tasa que el alquiler, lo que genera una alerta temprana sobre una posible formacion de burbuja de precios. La segundo etapa del analisis consistio en estimar un modelo econometrico, en donde se buscaba explicar el movimiento del precio a partir de variables fundamentales de oferta y demanda: salario de la construccion, costos de la construccion, rendimiento de otros activos, tasa de interes de los creditos para vivienda y el indice de actividad economica (IDEAC). El resultado del modelo mostro que la subida de precios es explicada por los fundamentales de oferta y demanda en un 93%, luego de aplicar tests de cointegracion y de estabilidad de parametros. Basados en los resultados, concluimos que no hay evidencia de que las expectativas de los agentes sobre apreciacion futura de las viviendas sea el principal factor explicativo de la subida de precios; con lo cual rechazamos la hipotesis de formacion de una burbuja inmobiliaria en el Ecuador, de manera agregada.English Abstract: This study analyzes the evolution of aggregate prices in Ecuadorian housing market, using secondary data, since January 2008 to October 2014. The Price to Earnings Ratio (PER), used to comparatively assess stock prices, was adapted to the housing market as the ratio Price/Rent. The PER showed that housing prices have increased in greater proportion than rent, generating an early warning of an eventual bubble. The second stage of the analysis was to estimate an econometric model, which sought to explain the price movement from fundamentals of supply and demand: construction wages, construction costs, return over other assets, interest rate for housing loans and the index of economic activity (IDEAC). The model results showed that the price increase is explained by the fundamentals of supply and demand by 93%, after applying cointegration and parameters stability tests. Based on these results, we conclude that there is no evidence that agents expectations of future appreciation is the main factor explaining the aggregate price rise; thus rejecting the hypothesis of formation of a housing bubble in Ecuador.
{"title":"Existe Evidencia De Burbuja Inmobiliaria En El Ecuador? (Is There Evidence of a Housing Bubble in Ecuador?)","authors":"Washington Macías, L. Guzmán, M. Ramírez","doi":"10.2139/SSRN.2585716","DOIUrl":"https://doi.org/10.2139/SSRN.2585716","url":null,"abstract":"Spanish Abstract: El presente estudio analiza la evolucion de los precios del mercado de vivienda ecuatoriano de manera agregada, a partir de datos de fuentes secundarias, en el periodo enero 2008-octubre 2014. Se aplico el Price to Earnings Ratio (PER), utilizado en el analisis bursatil para valorar comparativamente las acciones, pero adaptado al mercado de vivienda como la relacion Precio/Alquiler. El PER mostro que los precios de la vivienda han crecido a mayor tasa que el alquiler, lo que genera una alerta temprana sobre una posible formacion de burbuja de precios. La segundo etapa del analisis consistio en estimar un modelo econometrico, en donde se buscaba explicar el movimiento del precio a partir de variables fundamentales de oferta y demanda: salario de la construccion, costos de la construccion, rendimiento de otros activos, tasa de interes de los creditos para vivienda y el indice de actividad economica (IDEAC). El resultado del modelo mostro que la subida de precios es explicada por los fundamentales de oferta y demanda en un 93%, luego de aplicar tests de cointegracion y de estabilidad de parametros. Basados en los resultados, concluimos que no hay evidencia de que las expectativas de los agentes sobre apreciacion futura de las viviendas sea el principal factor explicativo de la subida de precios; con lo cual rechazamos la hipotesis de formacion de una burbuja inmobiliaria en el Ecuador, de manera agregada.English Abstract: This study analyzes the evolution of aggregate prices in Ecuadorian housing market, using secondary data, since January 2008 to October 2014. The Price to Earnings Ratio (PER), used to comparatively assess stock prices, was adapted to the housing market as the ratio Price/Rent. The PER showed that housing prices have increased in greater proportion than rent, generating an early warning of an eventual bubble. The second stage of the analysis was to estimate an econometric model, which sought to explain the price movement from fundamentals of supply and demand: construction wages, construction costs, return over other assets, interest rate for housing loans and the index of economic activity (IDEAC). The model results showed that the price increase is explained by the fundamentals of supply and demand by 93%, after applying cointegration and parameters stability tests. Based on these results, we conclude that there is no evidence that agents expectations of future appreciation is the main factor explaining the aggregate price rise; thus rejecting the hypothesis of formation of a housing bubble in Ecuador.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"61 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-03-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84804133","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}
A modest approximation by homebuyers leads house prices to display three features that are present in the data but usually missing from perfectly rational models: momentum at one-year horizons, mean reversion at five-year horizons, and excess longer-term volatility relative to fundamentals. Valuing a house involves forecasting the current and future demand to live in the surrounding area. Buyers forecast using past transaction prices. Approximating buyers do not adjust for the expectations of past buyers, and instead assume that past prices reflect only contemporaneous demand, as with a capitalization rate formula. Consistent with survey evidence, this approximation leads buyers to expect increases in the market value of their homes after recent house price increases, to fail to anticipate the price busts that follow booms, and to be overconfident in their assessments of the housing market.
{"title":"An Extrapolative Model of House Price Dynamics","authors":"E. Glaeser, Charles G. Nathanson","doi":"10.2139/ssrn.2614539","DOIUrl":"https://doi.org/10.2139/ssrn.2614539","url":null,"abstract":"A modest approximation by homebuyers leads house prices to display three features that are present in the data but usually missing from perfectly rational models: momentum at one-year horizons, mean reversion at five-year horizons, and excess longer-term volatility relative to fundamentals. Valuing a house involves forecasting the current and future demand to live in the surrounding area. Buyers forecast using past transaction prices. Approximating buyers do not adjust for the expectations of past buyers, and instead assume that past prices reflect only contemporaneous demand, as with a capitalization rate formula. Consistent with survey evidence, this approximation leads buyers to expect increases in the market value of their homes after recent house price increases, to fail to anticipate the price busts that follow booms, and to be overconfident in their assessments of the housing market.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"24 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78709528","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 studies the role of housing markets in explaining recent current account dynamics. I document a strong negative correlation, both across and within countries, between housing and current account dynamics. Then, in a quantitative two-country model without exchange rate driven expenditure switching, I analyze savings glut shocks and three drivers of housing demand (population, loan-to-value and housing price expectations) for which I input their dynamics observed in the OECD economies since the mid 1990s. Housing drivers alone imply counterfactual interest rate dynamics. Savings glut shocks alone cannot account for the housing dynamics. The combination of both types of shocks allows to match the emergence and narrowing of the Global Imbalances and the housing booms and busts. Counterfactuals using the model suggest that, as long as loan-to-values are regulated and housing expectations are not very optimistic, the large global imbalances of the mid-2000s are unlikely to return.
{"title":"Housing Demands, Savings Gluts and Current Account Dynamics","authors":"Pedro Gete","doi":"10.24149/gwp221","DOIUrl":"https://doi.org/10.24149/gwp221","url":null,"abstract":"This paper studies the role of housing markets in explaining recent current account dynamics. I document a strong negative correlation, both across and within countries, between housing and current account dynamics. Then, in a quantitative two-country model without exchange rate driven expenditure switching, I analyze savings glut shocks and three drivers of housing demand (population, loan-to-value and housing price expectations) for which I input their dynamics observed in the OECD economies since the mid 1990s. Housing drivers alone imply counterfactual interest rate dynamics. Savings glut shocks alone cannot account for the housing dynamics. The combination of both types of shocks allows to match the emergence and narrowing of the Global Imbalances and the housing booms and busts. Counterfactuals using the model suggest that, as long as loan-to-values are regulated and housing expectations are not very optimistic, the large global imbalances of the mid-2000s are unlikely to return.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2015-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72679262","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}
House prices are usually characterized by periods of long-lasting growth that lead to uncertainty concerning their persistence. This uncertainty is of special importance for central banks: the prolonged periods of rise followed by sudden fall in house prices are often associated with a credit crunch and a long-lasting and painful recession. Furthermore, monetary policy - incorrectly assessing the persistence of house prices - may further amplify the impact of house prices on the economy. In order to analyze the costs of this mistake I compare the performance of two policy rules that are optimal under extreme assumptions: 1. there is a housing shock that leads to the persistent deviations of house prices from the long-run trend and 2. there is no such a shock and house prices deviate from the trend only due to the impact of other shocks. I show that the central bank minimizing these costs should act as if house prices persistently deviate from the trend. If the central bank incorrectly assumes that house prices change only because of other shocks it conducts too loose monetary policy that significantly increases fluctuations of output gap and inflation.
{"title":"To Believe or Not to Believe: Monetary Policy and the Trend in House Prices","authors":"Grzegorz Wesołowski","doi":"10.2139/ssrn.2646616","DOIUrl":"https://doi.org/10.2139/ssrn.2646616","url":null,"abstract":"House prices are usually characterized by periods of long-lasting growth that lead to uncertainty concerning their persistence. This uncertainty is of special importance for central banks: the prolonged periods of rise followed by sudden fall in house prices are often associated with a credit crunch and a long-lasting and painful recession. Furthermore, monetary policy - incorrectly assessing the persistence of house prices - may further amplify the impact of house prices on the economy. In order to analyze the costs of this mistake I compare the performance of two policy rules that are optimal under extreme assumptions: 1. there is a housing shock that leads to the persistent deviations of house prices from the long-run trend and 2. there is no such a shock and house prices deviate from the trend only due to the impact of other shocks. I show that the central bank minimizing these costs should act as if house prices persistently deviate from the trend. If the central bank incorrectly assumes that house prices change only because of other shocks it conducts too loose monetary policy that significantly increases fluctuations of output gap and inflation.","PeriodicalId":12014,"journal":{"name":"ERN: Microeconometric Studies of Housing Markets (Topic)","volume":"48 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2014-12-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88030592","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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