In the distribution of the Paycheck Protection Program’s (PPP) $803 billion in funds, FinTech lenders began minimally but ramped up their market share to over 80% of originated loans by the end of the program. We examine metrics related to potential misreporting including non-registered businesses, multiple businesses at residential addresses, abnormally high implied compensation per employee, and large inconsistencies in jobs reported with another government program. We assess these four metrics with five additional measures and extensive supporting analysis. FinTech loans exhibit sharp and discontinuous increases in misreporting at maximum loan thresholds and round loan amounts. FinTech loans are more than 3.5 times as likely to be initiated by someone with a criminal background, strongly cluster in industry-county pairs to a degree that is infeasible based on U.S. Census data on establishment counts, and frequently exhibit similar loan features within lender-county pairs. Certain FinTech lenders seem to specialize in questionable loans with more than 40% of their loans experiencing at least one misreporting indicator. Few of these loans have been prosecuted by authorities or repaid. FinTech lenders with the highest misreporting in the first two rounds of the program in 2020 increase both their market share and their misreporting substantially in the third round in 2021. While FinTech lenders likely expand PPP access, this may come at the cost of facilitating fraudulent credit.
{"title":"Did FinTech Lenders Facilitate PPP Fraud?","authors":"J. Griffin, Samuel Kruger, Prateek Mahajan","doi":"10.2139/ssrn.3906395","DOIUrl":"https://doi.org/10.2139/ssrn.3906395","url":null,"abstract":"In the distribution of the Paycheck Protection Program’s (PPP) $803 billion in funds, FinTech lenders began minimally but ramped up their market share to over 80% of originated loans by the end of the program. We examine metrics related to potential misreporting including non-registered businesses, multiple businesses at residential addresses, abnormally high implied compensation per employee, and large inconsistencies in jobs reported with another government program. We assess these four metrics with five additional measures and extensive supporting analysis. FinTech loans exhibit sharp and discontinuous increases in misreporting at maximum loan thresholds and round loan amounts. FinTech loans are more than 3.5 times as likely to be initiated by someone with a criminal background, strongly cluster in industry-county pairs to a degree that is infeasible based on U.S. Census data on establishment counts, and frequently exhibit similar loan features within lender-county pairs. Certain FinTech lenders seem to specialize in questionable loans with more than 40% of their loans experiencing at least one misreporting indicator. Few of these loans have been prosecuted by authorities or repaid. FinTech lenders with the highest misreporting in the first two rounds of the program in 2020 increase both their market share and their misreporting substantially in the third round in 2021. While FinTech lenders likely expand PPP access, this may come at the cost of facilitating fraudulent credit.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"88 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84158387","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}
Does financial reform improve public good provision? We examine state-level adoption of municipal bankruptcy law. After reform, municipalities’ borrowing costs decrease and bonds’ issuance increase, particularly for bonds financing hospitals; hospitals’ investments increase, particularly when using such bonds; local firms’ investment and performance increase, particularly in the construction sector. Ex ante, reform occurs earlier in states with weaker unions, stronger bondholders’ interests, and better courts. Similar factors explain congressional voting on municipal bankruptcy law. These results support the hypothesis that financial reform destroys labor union rents and expands investment, highlighting a novel spillover channel from public finance to the real economy. This paper was accepted by Victoria Ivashina, finance. Funding: This work was supported by the Baffi-CAREFIN Research Center at Bocconi. Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mnsc.2023.4800 .
{"title":"Financial Reform and Public Good Provision: Municipal Bankruptcy Law and the Financing of Hospitals","authors":"Stefano Rossi, Hayong Yun","doi":"10.2139/ssrn.2698665","DOIUrl":"https://doi.org/10.2139/ssrn.2698665","url":null,"abstract":"Does financial reform improve public good provision? We examine state-level adoption of municipal bankruptcy law. After reform, municipalities’ borrowing costs decrease and bonds’ issuance increase, particularly for bonds financing hospitals; hospitals’ investments increase, particularly when using such bonds; local firms’ investment and performance increase, particularly in the construction sector. Ex ante, reform occurs earlier in states with weaker unions, stronger bondholders’ interests, and better courts. Similar factors explain congressional voting on municipal bankruptcy law. These results support the hypothesis that financial reform destroys labor union rents and expands investment, highlighting a novel spillover channel from public finance to the real economy. This paper was accepted by Victoria Ivashina, finance. Funding: This work was supported by the Baffi-CAREFIN Research Center at Bocconi. Supplemental Material: The data files and online appendix are available at https://doi.org/10.1287/mnsc.2023.4800 .","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"107 3 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75298263","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}
On the issue of insurance discrimination, a grey area in regulation has resulted from the growing use of big data analytics by insurance companies – direct discrimination is prohibited, but indirect discrimination using proxies or more complex and opaque algorithms can be tolerated without restrictions. Meanwhile, various fairness criteria have been proposed and flourish in the machine learning literature with the rapid growth of artificial intelligence (AI) in the past decade, which generally focus on a classification decision. However, there is little research on insurance applications, particularly on insurance pricing as a regression problem. In this paper, we summarise the fairness criteria that are potentially applicable to insurance pricing, match them with different levels of anti-discrimination regulations, and implement them into a series of existing and newly proposed anti-discrimination insurance pricing models. Our empirical analysis compares the outcome of different models and shows the potential of indirect discrimination.
{"title":"Anti-Discrimination Insurance Pricing: Regulations, Fairness Criteria, and Models","authors":"Xin Xin, Fei Huang","doi":"10.2139/ssrn.3850420","DOIUrl":"https://doi.org/10.2139/ssrn.3850420","url":null,"abstract":"On the issue of insurance discrimination, a grey area in regulation has resulted from the growing use of big data analytics by insurance companies – direct discrimination is prohibited, but indirect discrimination using proxies or more complex and opaque algorithms can be tolerated without restrictions. Meanwhile, various fairness criteria have been proposed and flourish in the machine learning literature with the rapid growth of artificial intelligence (AI) in the past decade, which generally focus on a classification decision. However, there is little research on insurance applications, particularly on insurance pricing as a regression problem. In this paper, we summarise the fairness criteria that are potentially applicable to insurance pricing, match them with different levels of anti-discrimination regulations, and implement them into a series of existing and newly proposed anti-discrimination insurance pricing models. Our empirical analysis compares the outcome of different models and shows the potential of indirect discrimination.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"62 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89904634","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}
Using employer-employee level data linked to individual health records, we document that the incidence of stress, anxiety, depression, psychiatric medication usage, and even suicide increase following acquisitions. These effects are prevalent among employees from both targets and acquirers, in weak as well as in growing, profitable firms. Employees who experience negative career developments within the merging firms, 'blue-collar' workers, and employees with lower cognitive and non-cognitive skills are most affected. A variety of tests address endogeneity concerns, including an analysis exploiting failed mergers. Our findings point to mental illness as a significant non-pecuniary cost of acquisitions.
{"title":"How Do Acquisitions Affect the Mental Health of Employees?","authors":"L. Bach, Ramin P. Baghai, M. Bos, Rui C. Silva","doi":"10.2139/ssrn.3940462","DOIUrl":"https://doi.org/10.2139/ssrn.3940462","url":null,"abstract":"Using employer-employee level data linked to individual health records, we document that the incidence of stress, anxiety, depression, psychiatric medication usage, and even suicide increase following acquisitions. These effects are prevalent among employees from both targets and acquirers, in weak as well as in growing, profitable firms. Employees who experience negative career developments within the merging firms, 'blue-collar' workers, and employees with lower cognitive and non-cognitive skills are most affected. A variety of tests address endogeneity concerns, including an analysis exploiting failed mergers. Our findings point to mental illness as a significant non-pecuniary cost of acquisitions.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"42 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78728413","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}
Using a plausibly exogenous shock to performance disclosure frequency by listed brokerage houses in China, we examine the impact of disclosure frequency on the quality of information production. Difference-in-difference estimation shows that analysts affiliated with listed brokerage houses exhibit lower forecast optimism in the post-regulation period, compared to their unlisted peers. Cross-sectional analyses suggest that the effect is more pronounced when the listed brokerage houses’ business relies less on their clients, when analysts have greater career concern, and when the covered firms exhibit lower valuation uncertainty/difficulty. Additional analysis indicates that forecast revisions by analysts affiliated with a listed brokerage house are more informative after the shock. Moreover, we find that analysts affiliated with listed brokerage houses issue more accurate and frequent forecasts and cover more companies than their peers do, which suggests that information production improves as a result of increased competition. Overall, our evidence suggests that increased performance disclosure by information intermediaries has positive externalities.
{"title":"The Unintended Benefits of Increased Disclosure Frequency: Evidence from the Brokerage House Industry","authors":"Yan Hu, Xiaoxi Li, Wei Shi","doi":"10.2139/ssrn.3935185","DOIUrl":"https://doi.org/10.2139/ssrn.3935185","url":null,"abstract":"Using a plausibly exogenous shock to performance disclosure frequency by listed brokerage houses in China, we examine the impact of disclosure frequency on the quality of information production. Difference-in-difference estimation shows that analysts affiliated with listed brokerage houses exhibit lower forecast optimism in the post-regulation period, compared to their unlisted peers. Cross-sectional analyses suggest that the effect is more pronounced when the listed brokerage houses’ business relies less on their clients, when analysts have greater career concern, and when the covered firms exhibit lower valuation uncertainty/difficulty. Additional analysis indicates that forecast revisions by analysts affiliated with a listed brokerage house are more informative after the shock. Moreover, we find that analysts affiliated with listed brokerage houses issue more accurate and frequent forecasts and cover more companies than their peers do, which suggests that information production improves as a result of increased competition. Overall, our evidence suggests that increased performance disclosure by information intermediaries has positive externalities.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"1 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-10-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82730833","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}
David Benson, Samuel Blattner, Serafin Grundl, You Suk Kim, Ken Onishi
Market concentration (HHI) based antitrust policy can be vulnerable to mismeasurement of substitutability. We provide evidence demonstrating this vulnerability in the banking industry, and argue that HHI-based bank antitrust review can be improved by incorporating a determinant of substitutability between merging banks: the proximity of their branch networks. Using difference-in-differences to estimate the effects of bank mergers, we find that mergers of close-proximity banks lead to more branch closures and to repositioning that is less beneficial for consumer access. Moreover, although rivals offer worse interest rates (prices) after close-proximity mergers, the merging parties' deposit growth (quantity) declines. These results hold for transactions that evade HHI-based enforcement criteria. Our findings also inform antitrust policy for other industries where firms’ locations are an important and observable determinant of substitutability.
{"title":"Concentration and Geographic Proximity in Antitrust Policy: Evidence from Bank Mergers","authors":"David Benson, Samuel Blattner, Serafin Grundl, You Suk Kim, Ken Onishi","doi":"10.2139/ssrn.3873502","DOIUrl":"https://doi.org/10.2139/ssrn.3873502","url":null,"abstract":"Market concentration (HHI) based antitrust policy can be vulnerable to mismeasurement of substitutability. We provide evidence demonstrating this vulnerability in the banking industry, and argue that HHI-based bank antitrust review can be improved by incorporating a determinant of substitutability between merging banks: the proximity of their branch networks. Using difference-in-differences to estimate the effects of bank mergers, we find that mergers of close-proximity banks lead to more branch closures and to repositioning that is less beneficial for consumer access. Moreover, although rivals offer worse interest rates (prices) after close-proximity mergers, the merging parties' deposit growth (quantity) declines. These results hold for transactions that evade HHI-based enforcement criteria. Our findings also inform antitrust policy for other industries where firms’ locations are an important and observable determinant of substitutability.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"7 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84290416","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}
Evangelos Vasileiou, Theodore Syriopoulos, P. Vlachou, M. Tsatsaronis, Angeliki Papaprokopiou
This analysis tests whether the quantitative requirements of the law (Basel and Committee of European Securities Regulators) regarding the Value at Risk (VaR) framework may lead to inaccurate and procyclical VaR estimations. We apply two of the most popular VaR models, the Historical (HVaR) and the Exponential Weighted Moving Average (EWMA VaR) models, to a wide sample of 13 European Indices during the period 2002-2019. The empirical evidence confirms our assumptions that the legal framework in many cases leads to inaccurate and procyclical VaR estimations. Moreover, we show that the limitation on the required data inputs does not really contribute to a more stable financial environment. Further, we show that the current framework does not examine the procyclicality issue. The evidence in this study shows that the current legal framework needs some reforms: (a) the guideline on the minimum number of data inputs for the VaR estimations should be removed, taking provided that the accuracy of the applied VaR model is often evaluated, and (b) the current backtesting procedure does not examine whether VaR estimations are representative of the financial conditions. An additional backtesting procedure at a lower that the 99% confidence level could resolve this issue.
{"title":"Does the Value-at-Risk legal framework lead to inaccurate and procyclical risk estimations? Empirical Evidence from the EU countries.","authors":"Evangelos Vasileiou, Theodore Syriopoulos, P. Vlachou, M. Tsatsaronis, Angeliki Papaprokopiou","doi":"10.2139/ssrn.3926785","DOIUrl":"https://doi.org/10.2139/ssrn.3926785","url":null,"abstract":"This analysis tests whether the quantitative requirements of the law (Basel and Committee of European Securities Regulators) regarding the Value at Risk (VaR) framework may lead to inaccurate and procyclical VaR estimations. We apply two of the most popular VaR models, the Historical (HVaR) and the Exponential Weighted Moving Average (EWMA VaR) models, to a wide sample of 13 European Indices during the period 2002-2019. The empirical evidence confirms our assumptions that the legal framework in many cases leads to inaccurate and procyclical VaR estimations. Moreover, we show that the limitation on the required data inputs does not really contribute to a more stable financial environment. Further, we show that the current framework does not examine the procyclicality issue. The evidence in this study shows that the current legal framework needs some reforms: (a) the guideline on the minimum number of data inputs for the VaR estimations should be removed, taking provided that the accuracy of the applied VaR model is often evaluated, and (b) the current backtesting procedure does not examine whether VaR estimations are representative of the financial conditions. An additional backtesting procedure at a lower that the 99% confidence level could resolve this issue.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"55 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77220370","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 article discusses the European Commission’s proposal for a pilot regime for market infrastructures to experiment with the distributed ledger technology (DLT). In this respect, the article comments on the purpose, scope, requirements, and attention points for market operators, investment firms, and central securities depositories (CSDs) that are considering using this technology.The proposed requirements aim to provide legal certainty, ensure investor protection, support innovation, and protect financial stability. The European Commission attempt to reach these goals by establishing uniform requirements for DLT market infrastructures. This article advocates, however, that a level playing field between the various market participants using the technology should be warranted.
{"title":"A European DLT Pilot Regime for Market Infrastructures: Finding a Balance Between Innovation, Investor Protection, and Financial Stability","authors":"Randy Priem","doi":"10.2139/ssrn.3919484","DOIUrl":"https://doi.org/10.2139/ssrn.3919484","url":null,"abstract":"This article discusses the European Commission’s proposal for a pilot regime for market infrastructures to experiment with the distributed ledger technology (DLT). In this respect, the article comments on the purpose, scope, requirements, and attention points for market operators, investment firms, and central securities depositories (CSDs) that are considering using this technology.The proposed requirements aim to provide legal certainty, ensure investor protection, support innovation, and protect financial stability. The European Commission attempt to reach these goals by establishing uniform requirements for DLT market infrastructures. This article advocates, however, that a level playing field between the various market participants using the technology should be warranted.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86718567","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 present a new database of banking-crisis interventions since the 13th century. The database includes 1886 interventions in 20 categories across 138 countries, covering interventions during all of the crises identified in the main banking-crisis chronologies, while also cataloguing a large number of interventions outside of those crises. The data show a gradual shift over the past centuries from the traditional interventions of a lender-of-last-resort, suspensions of convertibility, and bank holidays, towards a much more prominent role for capital injections and sweeping guarantees of bank liabilities. Furthermore, intervention frequencies and sizes suggest that the crisis problem in the financial sector has indeed reached an apex during the post-Bretton Woods era – but that such trends are part of a more deeply entrenched development that saw global intervention frequencies and sizes gradually rise since at least the late 17th century.
{"title":"Banking-Crisis Interventions, 1257 - 2019","authors":"Andrew Metrick, Paul Schmelzing","doi":"10.2139/ssrn.3919264","DOIUrl":"https://doi.org/10.2139/ssrn.3919264","url":null,"abstract":"We present a new database of banking-crisis interventions since the 13th century. The database includes 1886 interventions in 20 categories across 138 countries, covering interventions during all of the crises identified in the main banking-crisis chronologies, while also cataloguing a large number of interventions outside of those crises. The data show a gradual shift over the past centuries from the traditional interventions of a lender-of-last-resort, suspensions of convertibility, and bank holidays, towards a much more prominent role for capital injections and sweeping guarantees of bank liabilities. Furthermore, intervention frequencies and sizes suggest that the crisis problem in the financial sector has indeed reached an apex during the post-Bretton Woods era – but that such trends are part of a more deeply entrenched development that saw global intervention frequencies and sizes gradually rise since at least the late 17th century.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"41 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74587825","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}
Using a large sample of Florida restaurants, we document significant racial disparities in the utilization of the Paycheck Protection Program (PPP). Only a small fraction of these disparities can be explained by distance to bank branches. Within the same ZIP code, Black- and Hispanic-owned firms are 20.5% and 7.0% less likely than white-owned firms to receive PPP loans. These disparities in PPP utilization are driven by disparities in bank lending, which are greater in counties in which white people exhibit more racial bias against Black people. In these more racially biased counties, Black-owned businesses substitute to nonbank PPP loans and loans provided directly by the Small Business Administration through its Economic Injury Disaster Loan program.
{"title":"Racial Disparities in the Paycheck Protection Program","authors":"S. Chernenko, D. Scharfstein","doi":"10.2139/ssrn.3907575","DOIUrl":"https://doi.org/10.2139/ssrn.3907575","url":null,"abstract":"Using a large sample of Florida restaurants, we document significant racial disparities in the utilization of the Paycheck Protection Program (PPP). Only a small fraction of these disparities can be explained by distance to bank branches. Within the same ZIP code, Black- and Hispanic-owned firms are 20.5% and 7.0% less likely than white-owned firms to receive PPP loans. These disparities in PPP utilization are driven by disparities in bank lending, which are greater in counties in which white people exhibit more racial bias against Black people. In these more racially biased counties, Black-owned businesses substitute to nonbank PPP loans and loans provided directly by the Small Business Administration through its Economic Injury Disaster Loan program.","PeriodicalId":20999,"journal":{"name":"Regulation of Financial Institutions eJournal","volume":"43 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-08-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90681566","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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