We study the efficiency of non-compete agreements (NCAs) in an equilibrium model of labor turnover. The model is consistent with empirical studies showing that NCAs reduce turnover, average wages, and wage dispersion for low-wage workers. But the model also predicts that NCAs, by reducing turnover, raise recruitment and employment. We show that optimal NCA policy: (i) is characterized by a Hosios like condition that balances the benefits of higher employment against the costs of inefficient congestion and poaching; (ii) depends critically on the minimum wage, such that enforcing NCAs can be efficient with a sufficiently high minimum wage; and (iii) alone cannot always achieve efficiency, also true of a minimum wage-yet with both instruments efficiency is always attainable. To guide policy makers, we derive a sufficient statistic in the form of an easily computed employment threshold above which NCAs are necessarily inefficiently restrictive, and show that employment levels in current low-wage U.S. labor markets are typically above this threshold. Finally, we calibrate the model to show that Oregon's 2008 ban of NCAs for low-wage workers increased welfare, albeit modestly (by roughly 0.1%), and that if policy makers had also raised the minimum wage to its optimal level (a 30% increase), welfare would have increased more substantially-by over 1%.
{"title":"On the Inefficiency of Non-Competes in Low-Wage Labor Markets","authors":"Tristan Potter, B. Hobijn, André Kurmann","doi":"10.24148/wp2022-01","DOIUrl":"https://doi.org/10.24148/wp2022-01","url":null,"abstract":"We study the efficiency of non-compete agreements (NCAs) in an equilibrium model of labor turnover. The model is consistent with empirical studies showing that NCAs reduce turnover, average wages, and wage dispersion for low-wage workers. But the model also predicts that NCAs, by reducing turnover, raise recruitment and employment. We show that optimal NCA policy: (i) is characterized by a Hosios like condition that balances the benefits of higher employment against the costs of inefficient congestion and poaching; (ii) depends critically on the minimum wage, such that enforcing NCAs can be efficient with a sufficiently high minimum wage; and (iii) alone cannot always achieve efficiency, also true of a minimum wage-yet with both instruments efficiency is always attainable. To guide policy makers, we derive a sufficient statistic in the form of an easily computed employment threshold above which NCAs are necessarily inefficiently restrictive, and show that employment levels in current low-wage U.S. labor markets are typically above this threshold. Finally, we calibrate the model to show that Oregon's 2008 ban of NCAs for low-wage workers increased welfare, albeit modestly (by roughly 0.1%), and that if policy makers had also raised the minimum wage to its optimal level (a 30% increase), welfare would have increased more substantially-by over 1%.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-01-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127059252","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 use county panel data to study the dynamic responses of local economies after natural disasters in the U.S. Specifically, we estimate disaster impulse response functions for personal income per capita and a broad range of other economic outcomes, using a panel version of the local projections estimator. In contrast to some recent cross-country studies, we find that disasters increase total and per capita personal income over the longer-run (as of 8 years out). The effect is driven initially largely by a temporary employment boost and in the longer run by an increase in average weekly wages. We then assess the heterogeneity of disaster impacts across several dimensions. We find that the longer-run increase in income per capita rises with disaster severity, as measured by monetary damages. Hurricanes, tornados, and fires yield longer run increases in income, while floods do not. The longer run increase in income tends to rise with recent disaster experience and is absent for counties with no recent experience. Finally, a spatial spillover analysis suggests that, while over the short- to medium-run, the regional and local impacts of disasters on personal income are similar, over the longer run the net regional effect may be negative, in contrast to the positive local effect.
{"title":"The Local Economic Impact of Natural Disasters","authors":"Brigitte Roth Tran","doi":"10.24148/wp2020-34","DOIUrl":"https://doi.org/10.24148/wp2020-34","url":null,"abstract":"We use county panel data to study the dynamic responses of local economies after natural disasters in the U.S. Specifically, we estimate disaster impulse response functions for personal income per capita and a broad range of other economic outcomes, using a panel version of the local projections estimator. In contrast to some recent cross-country studies, we find that disasters increase total and per capita personal income over the longer-run (as of 8 years out). The effect is driven initially largely by a temporary employment boost and in the longer run by an increase in average weekly wages. We then assess the heterogeneity of disaster impacts across several dimensions. We find that the longer-run increase in income per capita rises with disaster severity, as measured by monetary damages. Hurricanes, tornados, and fires yield longer run increases in income, while floods do not. The longer run increase in income tends to rise with recent disaster experience and is absent for counties with no recent experience. Finally, a spatial spillover analysis suggests that, while over the short- to medium-run, the regional and local impacts of disasters on personal income are similar, over the longer run the net regional effect may be negative, in contrast to the positive local effect.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125863706","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}
Theory suggests that initial public offerings (IPOs) can adversely impact listed firms, both directly by increasing intra-industry competition, and in-directly by completing related asset market spaces. However, the endogeneity of individual IPO activity hinders testing these channels. This paper examines listing suspensions in China in a panel specification that accounts for macroeconomic and financial conditions, isolating the firm-level IPO impact. We measure the competi-tive impact of listing suspensions through the value share of postponed firms in the IPO queue in their industry, and asset-space competition by firms’ historical covariance with a synthetic portfolio of listed firms with the IPO queue industry mix at the time of suspension. Our results support the predicted IPO effects through both channels. We also document heterogeneity in IPO effects. Stronger firms–measured through a variety of proxies–benefit less from the suspension news. These results are robust to a battery of sensitivity tests
{"title":"Competitive Effects of IPOS: Evidence from Chinese Listing Suspensions","authors":"Frank Packer, M. Spiegel","doi":"10.24148/WP2020-30","DOIUrl":"https://doi.org/10.24148/WP2020-30","url":null,"abstract":"Theory suggests that initial public offerings (IPOs) can adversely impact listed firms, both directly by increasing intra-industry competition, and in-directly by completing related asset market spaces. However, the endogeneity of individual IPO activity hinders testing these channels. This paper examines listing suspensions in China in a panel specification that accounts for macroeconomic and financial conditions, isolating the firm-level IPO impact. We measure the competi-tive impact of listing suspensions through the value share of postponed firms in the IPO queue in their industry, and asset-space competition by firms’ historical covariance with a synthetic portfolio of listed firms with the IPO queue industry mix at the time of suspension. Our results support the predicted IPO effects through both channels. We also document heterogeneity in IPO effects. Stronger firms–measured through a variety of proxies–benefit less from the suspension news. These results are robust to a battery of sensitivity tests","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-09-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130088186","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 proposes a simple framework to help monitor and understand movements in PCE inflation in real time. The approach is to decompose inflation using simple categorical-level regressions or systems of equations. The estimates are then used to group categories into components of PCE inflation. I review some applications of the methodology, and show how it can help explain inflation dynamics over recent episodes. The methodology shows that inflation remained low in the mid-2010s primarily because of factors unrelated to aggregate economic conditions. I also apply the methodology to the Covid-19 pandemic. The decomposition reveals that a majority of the drop in core PCE inflation after the onset of the pandemic was attributable to an initial strong decline in consumer demand, which more recently has rebounded somewhat.
{"title":"A Simple Framework to Monitor Inflation","authors":"A. Shapiro","doi":"10.24148/wp2020-29","DOIUrl":"https://doi.org/10.24148/wp2020-29","url":null,"abstract":"This paper proposes a simple framework to help monitor and understand movements in PCE inflation in real time. The approach is to decompose inflation using simple categorical-level regressions or systems of equations. The estimates are then used to group categories into components of PCE inflation. I review some applications of the methodology, and show how it can help explain inflation dynamics over recent episodes. The methodology shows that inflation remained low in the mid-2010s primarily because of factors unrelated to aggregate economic conditions. I also apply the methodology to the Covid-19 pandemic. The decomposition reveals that a majority of the drop in core PCE inflation after the onset of the pandemic was attributable to an initial strong decline in consumer demand, which more recently has rebounded somewhat.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"329 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-08-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124636486","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}
Aggregate bank lending to firms expands following adverse macroeconomic shocks, such as the outbreak of COVID-19 or a monetary policy tightening, at odds with canonical models. Using loan-level supervisory data, we show that these dynamics are driven by draws on credit lines by large firms. Banks that experience larger drawdowns restrict term lending more — an externality onto smaller firms. Using a structural model, we show that credit lines are necessary to reproduce the flow of credit toward less constrained firms after adverse shocks. While credit lines increase total credit growth, their redistributive effects exacerbate the fall in investment.
{"title":"The Credit Line Channel","authors":"Daniel L. Greenwald, John Krainer, Pascal Paul","doi":"10.24148/wp2020-26","DOIUrl":"https://doi.org/10.24148/wp2020-26","url":null,"abstract":"Aggregate bank lending to firms expands following adverse macroeconomic shocks, such as the outbreak of COVID-19 or a monetary policy tightening, at odds with canonical models. Using loan-level supervisory data, we show that these dynamics are driven by draws on credit lines by large firms. Banks that experience larger drawdowns restrict term lending more — an externality onto smaller firms. Using a structural model, we show that credit lines are necessary to reproduce the flow of credit toward less constrained firms after adverse shocks. While credit lines increase total credit growth, their redistributive effects exacerbate the fall in investment.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115095823","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 : 2020-07-02DOI: 10.1101/2020.07.23.20160911
Daniel J. Wilson
Using high-frequency panel data for U.S. counties, I estimate the full dynamic response of COVID-19 cases and deaths to exogenous movements in mobility and weather. I find several important results. First, holding mobility fixed, temperature is found to have a negative and significant effect on COVID-19 cases from 1 to 8 weeks ahead and on deaths from 2 to 8 weeks ahead. Second, holding weather fixed, mobility is found to have a large positive effect on subsequent growth in COVID-19 cases and deaths. The impact on cases becomes significant 3 to 4 weeks ahead and continues through 8 to 10 weeks ahead. The impact on deaths becomes significant around 4 weeks ahead and persists for at least 10 weeks. Third, I find that the deleterious effects of mobility on COVID-19 outcomes are far greater when the local virus transmission rate is above one -- evidence supportive of public health policies aiming to reduce mobility specifically in places experiencing high transmission rates while relaxing restrictions elsewhere. Fourth, I find that the dynamic effects of mobility on cases are generally similar across counties, but the effects on deaths are higher for counties with older populations and, surprisingly, counties with lower black or hispanic population shares. Lastly, I find that while the marginal impact of mobility changes has been stable over recent weeks for cases, it has come down for deaths.
{"title":"Weather, Social Distancing, and the Spread ofCOVID-19","authors":"Daniel J. Wilson","doi":"10.1101/2020.07.23.20160911","DOIUrl":"https://doi.org/10.1101/2020.07.23.20160911","url":null,"abstract":"Using high-frequency panel data for U.S. counties, I estimate the full dynamic response of COVID-19 cases and deaths to exogenous movements in mobility and weather. I find several important results. First, holding mobility fixed, temperature is found to have a negative and significant effect on COVID-19 cases from 1 to 8 weeks ahead and on deaths from 2 to 8 weeks ahead. Second, holding weather fixed, mobility is found to have a large positive effect on subsequent growth in COVID-19 cases and deaths. The impact on cases becomes significant 3 to 4 weeks ahead and continues through 8 to 10 weeks ahead. The impact on deaths becomes significant around 4 weeks ahead and persists for at least 10 weeks. Third, I find that the deleterious effects of mobility on COVID-19 outcomes are far greater when the local virus transmission rate is above one -- evidence supportive of public health policies aiming to reduce mobility specifically in places experiencing high transmission rates while relaxing restrictions elsewhere. Fourth, I find that the dynamic effects of mobility on cases are generally similar across counties, but the effects on deaths are higher for counties with older populations and, surprisingly, counties with lower black or hispanic population shares. Lastly, I find that while the marginal impact of mobility changes has been stable over recent weeks for cases, it has come down for deaths.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125328071","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 Great Recession and current pandemic have focused attention on the constraint on nominal interest rates from the effective lower bound. This has renewed interest in monetary policies that embed makeup strategies, such as price-level or average-inflation targeting. This paper examines the properties of average-inflation targeting in a two-agent New Keynesian (TANK) model in which a fraction of firms have adaptive expectations. We examine the optimal degree of history dependence under average-inflation targeting and find it to be relatively short for business cycle shocks of standard magnitude and duration. In this case, we show that the properties of the economy are quantitatively similar to those under a price-level target.
{"title":"Average Is Good Enough: Average-Inflation Targeting and the ELB","authors":"R. Amano, S. Gnocchi, S. Leduc, Joël Wagner","doi":"10.24148/wp2020-21","DOIUrl":"https://doi.org/10.24148/wp2020-21","url":null,"abstract":"The Great Recession and current pandemic have focused attention on the constraint on nominal interest rates from the effective lower bound. This has renewed interest in monetary policies that embed makeup strategies, such as price-level or average-inflation targeting. This paper examines the properties of average-inflation targeting in a two-agent New Keynesian (TANK) model in which a fraction of firms have adaptive expectations. We examine the optimal degree of history dependence under average-inflation targeting and find it to be relatively short for business cycle shocks of standard magnitude and duration. In this case, we show that the properties of the economy are quantitatively similar to those under a price-level target.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124800722","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 the years since the Great Recession, many observers have highlighted the slow pace of labor and total factor productivity (TFP) growth in advanced economies. This paper focuses on the European experience, where we highlight that trend TFP growth was already low in the runup to the Global Financial Crisis (GFC). This suggests that it is important to consider factors other than just the deep crisis itself or policy changes since the crisis. After the mid-1990s, European economies stopped converging, or even began diverging, from the U.S. level of TFP. That said, in contrast to the United States, there is some macroeconomic evidence for some northern European countries that the GFC had a further adverse impact on TFP growth. Still, the challenges for economic policy look surprisingly similar to the ones discussed prior to the Great Recession, even if the policy implications seem less clear.
{"title":"Does Disappointing European Productivity Growth Reflect a Slowing Trend? Weighing the Evidence and Assessing the Future","authors":"John G. Fernald, R. Inklaar","doi":"10.24148/wp2020-22","DOIUrl":"https://doi.org/10.24148/wp2020-22","url":null,"abstract":"In the years since the Great Recession, many observers have highlighted the slow pace of labor and total factor productivity (TFP) growth in advanced economies. This paper focuses on the European experience, where we highlight that trend TFP growth was already low in the runup to the Global Financial Crisis (GFC). This suggests that it is important to consider factors other than just the deep crisis itself or policy changes since the crisis. After the mid-1990s, European economies stopped converging, or even began diverging, from the U.S. level of TFP. That said, in contrast to the United States, there is some macroeconomic evidence for some northern European countries that the GFC had a further adverse impact on TFP growth. Still, the challenges for economic policy look surprisingly similar to the ones discussed prior to the Great Recession, even if the policy implications seem less clear.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-06-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128914956","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 examine the distributional implications of capital account policy in a small open economy model with heterogeneous agents and financial frictions. Households save through deposits in both domestic and foreign banks. Entrepreneurs finance investment with borrowed funds from domestic banks and foreign investors. Domestic banks engage in costly intermediation of deposits from households and loans to entrepreneurs. Government capital account policy consists of taxes on outflows and inflows. Given policy, a temporary decline in the world interest rate leads to a surge in inflows, benefiting entrepreneurs and hurting households. Raising inflow taxes or reducing outflow taxes mitigate this redistribution. However, in the long run liberalization of either inflows or outflows reduces inequality. The model’s short-run implications are supported by empirical evidence. Based on instrumental variable estimation with a panel of emerging market economies, we demonstrate that increases in private capital inflows raise income inequality, while increases in outflows reduce it. These effects are significant and robust to a wide variety of empirical specifications.
{"title":"Capital Controls and Income Inequality","authors":"Zheng Liu, M. Spiegel, Jingyi Zhang","doi":"10.24148/wp2020-14","DOIUrl":"https://doi.org/10.24148/wp2020-14","url":null,"abstract":"We examine the distributional implications of capital account policy in a small open economy model with heterogeneous agents and financial frictions. Households save through deposits in both domestic and foreign banks. Entrepreneurs finance investment with borrowed funds from domestic banks and foreign investors. Domestic banks engage in costly intermediation of deposits from households and loans to entrepreneurs. Government capital account policy consists of taxes on outflows and inflows. Given policy, a temporary decline in the world interest rate leads to a surge in inflows, benefiting entrepreneurs and hurting households. Raising inflow taxes or reducing outflow taxes mitigate this redistribution. However, in the long run liberalization of either inflows or outflows reduces inequality. The model’s short-run implications are supported by empirical evidence. Based on instrumental variable estimation with a panel of emerging market economies, we demonstrate that increases in private capital inflows raise income inequality, while increases in outflows reduce it. These effects are significant and robust to a wide variety of empirical specifications.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121108946","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}
Total factor productivity (TFP) and investment specific technology (IST) growth both exhibit regime-switching behavior, but the regime at any given time is difficult to infer. We build a rational expectations real business cycle model where the underlying TFP and IST regimes are unobserved. We then develop a general perturbation solution algorithm for a wide class of models with unobserved regime-switching. Using our method, we show that learning about regime-switching alters the responses to regime shifts and intra-regime shocks, increases asymmetries in the responses, generates forecast error bias even with rational agents, and raises the welfare cost of fluctuations.
{"title":"Learning about Regime Change","authors":"Andrew T. Foerster, C. Matthes","doi":"10.24148/wp2020-15","DOIUrl":"https://doi.org/10.24148/wp2020-15","url":null,"abstract":"Total factor productivity (TFP) and investment specific technology (IST) growth both exhibit regime-switching behavior, but the regime at any given time is difficult to infer. We build a rational expectations real business cycle model where the underlying TFP and IST regimes are unobserved. We then develop a general perturbation solution algorithm for a wide class of models with unobserved regime-switching. Using our method, we show that learning about regime-switching alters the responses to regime shifts and intra-regime shocks, increases asymmetries in the responses, generates forecast error bias even with rational agents, and raises the welfare cost of fluctuations.","PeriodicalId":250744,"journal":{"name":"Federal Reserve Bank of San Francisco, Working Paper Series","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2020-04-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130394045","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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