We examine the extent and evolution of Hubris in a bank CEO, through textual analysis of the CEO letter to the Shareholders. Drawing on new developments in clinical psychology we surface evidence of overconfidence, narcissism and hubris over the 2000-2008 period.
{"title":"Is Executive Hubris Manifested in CEO Letters to Shareholders?","authors":"M. Devlin, B. Lucey","doi":"10.2139/ssrn.2833919","DOIUrl":"https://doi.org/10.2139/ssrn.2833919","url":null,"abstract":"We examine the extent and evolution of Hubris in a bank CEO, through textual analysis of the CEO letter to the Shareholders. Drawing on new developments in clinical psychology we surface evidence of overconfidence, narcissism and hubris over the 2000-2008 period.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"176 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-09-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132053330","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}
Option-based measures of overconfidence are widely used as proxies for overconfidence in corporate finance. Overexposure of a CEO's wealth to the firm's idiosyncratic risk is taken as a sign of CEO overconfidence. The literature has used the measures to study the effect of managerial overconfidence on corporate investment, financial policy, innovation and merger and acquisition. The belief is that overconfident CEOs behave differently. We trace CEOs across firms to investigate whether option exercise decisions correlate with firm characteristics. We find that a CEO's decision to hold or exercise vested options is considerably driven by firm and market conditions. Our analysis casts doubt on the view that repeated holding of in-the-money options solely captures overconfidence.
{"title":"Does CEO's Holding of Vested Options Measure Overconfidence?","authors":"A. Bayat, Reza Salehnejad, P. Kawalek","doi":"10.2139/ssrn.2825027","DOIUrl":"https://doi.org/10.2139/ssrn.2825027","url":null,"abstract":"Option-based measures of overconfidence are widely used as proxies for overconfidence in corporate finance. Overexposure of a CEO's wealth to the firm's idiosyncratic risk is taken as a sign of CEO overconfidence. The literature has used the measures to study the effect of managerial overconfidence on corporate investment, financial policy, innovation and merger and acquisition. The belief is that overconfident CEOs behave differently. We trace CEOs across firms to investigate whether option exercise decisions correlate with firm characteristics. We find that a CEO's decision to hold or exercise vested options is considerably driven by firm and market conditions. Our analysis casts doubt on the view that repeated holding of in-the-money options solely captures overconfidence.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-08-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114437441","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 growing consensus holds that cultural standards are at least as important as formal rules for the effectiveness and soundness of the banking sector. Nevertheless, the banking literature is mostly silent on cultural effects. We present an analysis of banking culture that draws upon prior sociological and economic work on organizational culture. We argue that the most important cultural practices in the financial services sector arose in response to pressing economic and social problems. But, once embedded into market activity, those practices became part of a toolkit that bankers could use in many contexts. In particular, after changes to the technological and legal environment within which bankers operate decoupled cultural practices from their original context, bankers started to deploy cultural devices in new fora where their social utility was less apparent. We examine this argument in the context of the LIBOR and Forex fixings, and we examine a number of policy prescriptions. The recent emphasis upon “tone from the top” is appropriate but, by itself, will be insufficient: culture can only be supervised and influenced by actors who are sufficiently immersed in it to decode the private languages upon which it is built.
{"title":"Governance and Culture in the Banking Sector","authors":"A. Morrison, Joel D. Shapiro","doi":"10.2139/ssrn.2731357","DOIUrl":"https://doi.org/10.2139/ssrn.2731357","url":null,"abstract":"A growing consensus holds that cultural standards are at least as important as formal rules for the effectiveness and soundness of the banking sector. Nevertheless, the banking literature is mostly silent on cultural effects. We present an analysis of banking culture that draws upon prior sociological and economic work on organizational culture. We argue that the most important cultural practices in the financial services sector arose in response to pressing economic and social problems. But, once embedded into market activity, those practices became part of a toolkit that bankers could use in many contexts. In particular, after changes to the technological and legal environment within which bankers operate decoupled cultural practices from their original context, bankers started to deploy cultural devices in new fora where their social utility was less apparent. We examine this argument in the context of the LIBOR and Forex fixings, and we examine a number of policy prescriptions. The recent emphasis upon “tone from the top” is appropriate but, by itself, will be insufficient: culture can only be supervised and influenced by actors who are sufficiently immersed in it to decode the private languages upon which it is built.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-02-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121295477","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
I test theories of the recent financial crisis by studying how banks' pre-crisis investments connect to their CEOs' beliefs. Using different proxies for beliefs, I find banks with larger housing investments and worse crisis performance had CEOs who were more optimistic ex ante. Banks with the most optimistic CEOs experienced 20 percentage points higher real estate loan growth, and 15 percentage points lower crisis period stock returns. Bank decisions appear consistent with CEO beliefs. CEOs' optimism contributed to credit expansions and crisis losses. I do not find evidence that CEOs made housing investments due to agency frictions while aware of impending problems.
{"title":"Bank CEO Optimism and the Financial Crisis","authors":"Yueran Ma","doi":"10.2139/ssrn.2392683","DOIUrl":"https://doi.org/10.2139/ssrn.2392683","url":null,"abstract":"I test theories of the recent financial crisis by studying how banks' pre-crisis investments connect to their CEOs' beliefs. Using different proxies for beliefs, I find banks with larger housing investments and worse crisis performance had CEOs who were more optimistic ex ante. Banks with the most optimistic CEOs experienced 20 percentage points higher real estate loan growth, and 15 percentage points lower crisis period stock returns. Bank decisions appear consistent with CEO beliefs. CEOs' optimism contributed to credit expansions and crisis losses. I do not find evidence that CEOs made housing investments due to agency frictions while aware of impending problems.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-09-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124512484","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 : 2015-07-25DOI: 10.4337/9781783474479.00020
Donald C. Langevoort
The design of an effective legal compliance system for an organization requires skill at predicting human behavior. The surveillance portion of compliance involves estimates about who is most likely to misbehave, and when. The communicative aspect — training and guidance — requires thinking about what kinds of messages and incentives are most effective. Forensics and resolution are about, at least in part, learning from the experience and applying the lessons to future activity. It’s entirely plausible to use the economist’s assumption of rational choice — opportunism with guile — in making these predictions. But the realism of that assumption has been under attack for decades now. The label “behavioral compliance” can be attached to the design and management of compliance that draws from a wider range of behavioral predictions about individual and organizational behavior. This chapter surveys some of the contemporary research in behavioral ethics, and its usefulness to the architecture of compliance.
{"title":"Behavioral Ethics, Behavioral Compliance","authors":"Donald C. Langevoort","doi":"10.4337/9781783474479.00020","DOIUrl":"https://doi.org/10.4337/9781783474479.00020","url":null,"abstract":"The design of an effective legal compliance system for an organization requires skill at predicting human behavior. The surveillance portion of compliance involves estimates about who is most likely to misbehave, and when. The communicative aspect — training and guidance — requires thinking about what kinds of messages and incentives are most effective. Forensics and resolution are about, at least in part, learning from the experience and applying the lessons to future activity. It’s entirely plausible to use the economist’s assumption of rational choice — opportunism with guile — in making these predictions. But the realism of that assumption has been under attack for decades now. The label “behavioral compliance” can be attached to the design and management of compliance that draws from a wider range of behavioral predictions about individual and organizational behavior. This chapter surveys some of the contemporary research in behavioral ethics, and its usefulness to the architecture of compliance.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"53 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-07-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115379959","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}
Eric de Bodt, Helen Bollaert, P. Grandin, Richard Roll
Firms may rationally select CEOs whose level of narcissism is compatible with their circumstances. We model the firm-CEO matching process in which narcissistic CEOs are matched to firms characterized by their shareholders’ risk aversion. This leads us to predict that (i) contemporaneous (future) CEO narcissism is increasing (decreasing) in the compensation package; (ii) CEO narcissism is decreasing in shareholder risk aversion and (iii) CEO narcissism is increasing in CEO narcissism mean reversion. We test our predictions on a 10-year sample of S&P 500 CEOs, using a time-varying measure of CEO narcissism. Our empirical results provide preliminary support for all our predictions.
{"title":"The Equilibrium Assignment of Narcissistic CEOs to Firms","authors":"Eric de Bodt, Helen Bollaert, P. Grandin, Richard Roll","doi":"10.2139/ssrn.2566708","DOIUrl":"https://doi.org/10.2139/ssrn.2566708","url":null,"abstract":"Firms may rationally select CEOs whose level of narcissism is compatible with their circumstances. We model the firm-CEO matching process in which narcissistic CEOs are matched to firms characterized by their shareholders’ risk aversion. This leads us to predict that (i) contemporaneous (future) CEO narcissism is increasing (decreasing) in the compensation package; (ii) CEO narcissism is decreasing in shareholder risk aversion and (iii) CEO narcissism is increasing in CEO narcissism mean reversion. We test our predictions on a 10-year sample of S&P 500 CEOs, using a time-varying measure of CEO narcissism. Our empirical results provide preliminary support for all our predictions.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-02-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115131426","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 investigate the association between managerial overconfidence and audit fees, as well as the effect of a strong audit committee on this relation. Overconfident managers tend to overestimate their ability and the future payouts of projects but underestimate the likelihood and impact of adverse events. If auditors perceive managerial overconfidence as increasing audit risk, they will charge additional fees to compensate for the increased audit effort. Conversely, audit fees for companies with an overconfident manager will be lower if managers demand less audit services due to either hubris in their companies' financial reporting or a desire to reduce auditor scrutiny over aggressive accounting practices. We find evidence of a negative relation between managerial overconfidence and audit fees for companies lacking a strong audit committee. Additionally, we find that overconfident managers are less likely to use an industry specialist auditor.
{"title":"Managerial Overconfidence and Audit Fees","authors":"Scott Duellman, Helen Hurwitz, Yan Sun","doi":"10.2139/ssrn.2557494","DOIUrl":"https://doi.org/10.2139/ssrn.2557494","url":null,"abstract":"We investigate the association between managerial overconfidence and audit fees, as well as the effect of a strong audit committee on this relation. Overconfident managers tend to overestimate their ability and the future payouts of projects but underestimate the likelihood and impact of adverse events. If auditors perceive managerial overconfidence as increasing audit risk, they will charge additional fees to compensate for the increased audit effort. Conversely, audit fees for companies with an overconfident manager will be lower if managers demand less audit services due to either hubris in their companies' financial reporting or a desire to reduce auditor scrutiny over aggressive accounting practices. We find evidence of a negative relation between managerial overconfidence and audit fees for companies lacking a strong audit committee. Additionally, we find that overconfident managers are less likely to use an industry specialist auditor.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124611533","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 essay introduces an innovative framework for consumer protection, based on consumers’ basic needs. Current contract law is based on a binary model: contracts which lack consent are considered void and are not enforceable under the unconscionability doctrine. Yet, voluntariness is not binary. Rather, voluntariness is a hierarchical continuum reflecting human needs. Certain products are purchased because the consumer has to have them, while other products are purchased as a discretionary consumer choice. Current law does not make the distinction between essential and non-essential markets. Consumers of luxuries and consumers of essentials are considered equal, and receive similar legal protection under the contractual framework of the consumer transaction. This essay offers a theory of essential markets and their regulation. The essay surveys the behavioral literature discussing human needs and the distinction between essentials and luxuries, and applies the needs-based theory to consumption, creating a pyramid of markets following Maslow’s hierarchy of needs. The essay identifies the determinants of market essentiality, including a moral baseline of consumption; lack of good substitutes and inability to decline purchase; and time constraints creating difficulty to defer purchase. The continuum of market essentiality is then demonstrated using four examples, including electricity for heating, infant formula, broadband services, and a violin. The essay argues that essential needs-based consumption induces a behavioral market failure, where consumers' decision-making process is particularly vulnerable and distorts sellers' incentives towards a sub-optimal equilibrium. Markets of essentials tend toward failure of demand, due to consumers’ bounded voluntariness and lower probability of informed choice. Accordingly, sellers in markets of essentials have higher incentives for collusion and lower incentives for price competition and for investment in product quality. Thus, the likelihood of market failure increases with the essentiality of the product: the more basic the underlying need, the higher the probability for market failure. The difficulty of regulators to tell which markets are essential is addressed. The essay suggests two methods for assessment of essentiality - the first, through political assessment, and the second, through analysis of market data documenting elasticity of demand for popular product categories. Low elasticity of demand for popular product categories is proposed as a market signal for consumers’ bounded voluntariness and for product essentiality. The normative implications of this structural division of markets are discussed and initial policy guidelines suggested. Essentiality and its tendency to create a behavioral market failure implies that consumer law should be structured with a hierarchy of rights, similar to constitutional or international human rights laws. Essential products should be subject to a higher degree
{"title":"A Hierarchy of Markets: How Basic Needs Induce a Market Failure","authors":"Shlomit Azgad-Tromer","doi":"10.2139/SSRN.2547995","DOIUrl":"https://doi.org/10.2139/SSRN.2547995","url":null,"abstract":"This essay introduces an innovative framework for consumer protection, based on consumers’ basic needs. Current contract law is based on a binary model: contracts which lack consent are considered void and are not enforceable under the unconscionability doctrine. Yet, voluntariness is not binary. Rather, voluntariness is a hierarchical continuum reflecting human needs. Certain products are purchased because the consumer has to have them, while other products are purchased as a discretionary consumer choice. Current law does not make the distinction between essential and non-essential markets. Consumers of luxuries and consumers of essentials are considered equal, and receive similar legal protection under the contractual framework of the consumer transaction. This essay offers a theory of essential markets and their regulation. The essay surveys the behavioral literature discussing human needs and the distinction between essentials and luxuries, and applies the needs-based theory to consumption, creating a pyramid of markets following Maslow’s hierarchy of needs. The essay identifies the determinants of market essentiality, including a moral baseline of consumption; lack of good substitutes and inability to decline purchase; and time constraints creating difficulty to defer purchase. The continuum of market essentiality is then demonstrated using four examples, including electricity for heating, infant formula, broadband services, and a violin. The essay argues that essential needs-based consumption induces a behavioral market failure, where consumers' decision-making process is particularly vulnerable and distorts sellers' incentives towards a sub-optimal equilibrium. Markets of essentials tend toward failure of demand, due to consumers’ bounded voluntariness and lower probability of informed choice. Accordingly, sellers in markets of essentials have higher incentives for collusion and lower incentives for price competition and for investment in product quality. Thus, the likelihood of market failure increases with the essentiality of the product: the more basic the underlying need, the higher the probability for market failure. The difficulty of regulators to tell which markets are essential is addressed. The essay suggests two methods for assessment of essentiality - the first, through political assessment, and the second, through analysis of market data documenting elasticity of demand for popular product categories. Low elasticity of demand for popular product categories is proposed as a market signal for consumers’ bounded voluntariness and for product essentiality. The normative implications of this structural division of markets are discussed and initial policy guidelines suggested. Essentiality and its tendency to create a behavioral market failure implies that consumer law should be structured with a hierarchy of rights, similar to constitutional or international human rights laws. Essential products should be subject to a higher degree","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"107 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132260602","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}
Understanding the role of culture in corporate governance has become a subject of growing importance. Today, no institutional analysis of corporate governance systems would be complete without considering the cultural environment in which such systems are embedded. This paper provides an overview of different accounts on how culture interacts with the law - especially corporate law - to shape corporate governance and on how this may help explain diversity and persistence in corporate governance. Basic concepts in cultural analysis are first presented, together with prevalent theories of cultural dimensions and of social networks as social capital. Relying on this analytical framework, this paper reviews current research on culture’s consequences for corporate governance on issues such as legal transplants, the objectives of the corporation (corporate social responsibility), relations with investors and other stakeholders by way of disclosure and dividend distribution, executive compensation, and the operation, composition, and network structure of the board of directors.
{"title":"Culture and Law in Corporate Governance","authors":"A. Licht","doi":"10.2139/SSRN.2405538","DOIUrl":"https://doi.org/10.2139/SSRN.2405538","url":null,"abstract":"Understanding the role of culture in corporate governance has become a subject of growing importance. Today, no institutional analysis of corporate governance systems would be complete without considering the cultural environment in which such systems are embedded. This paper provides an overview of different accounts on how culture interacts with the law - especially corporate law - to shape corporate governance and on how this may help explain diversity and persistence in corporate governance. Basic concepts in cultural analysis are first presented, together with prevalent theories of cultural dimensions and of social networks as social capital. Relying on this analytical framework, this paper reviews current research on culture’s consequences for corporate governance on issues such as legal transplants, the objectives of the corporation (corporate social responsibility), relations with investors and other stakeholders by way of disclosure and dividend distribution, executive compensation, and the operation, composition, and network structure of the board of directors.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-03-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133677496","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 analyzes the relation between chief executive officer (CEO) personal risk-taking, corporate risk-taking, and total firm risk. We find evidence that CEOs who possess private pilot licenses (our proxy for personal risk-taking) are associated with riskier firms. Firms led by pilot CEOs have higher equity return volatility, beyond the amount explained by compensation components that financially reward risk-taking. We trace the source of the elevated firm risk to specific corporate policies, including leverage and acquisition activity. Our results suggest that nonpecuniary risk preferences revealed outside the scope of the firm have implications for project selection and various corporate policies.
{"title":"CEO Personal Risk-Taking and Corporate Policies","authors":"Matthew D. Cain, S. McKeon","doi":"10.2139/ssrn.1785413","DOIUrl":"https://doi.org/10.2139/ssrn.1785413","url":null,"abstract":"This study analyzes the relation between chief executive officer (CEO) personal risk-taking, corporate risk-taking, and total firm risk. We find evidence that CEOs who possess private pilot licenses (our proxy for personal risk-taking) are associated with riskier firms. Firms led by pilot CEOs have higher equity return volatility, beyond the amount explained by compensation components that financially reward risk-taking. We trace the source of the elevated firm risk to specific corporate policies, including leverage and acquisition activity. Our results suggest that nonpecuniary risk preferences revealed outside the scope of the firm have implications for project selection and various corporate policies.","PeriodicalId":448402,"journal":{"name":"Corporate Governance & Sociology or Psychology eJournal","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-02-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115384069","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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