A theory of systemic risk and design of prudential bank regulation

Systemic risk is modeled as the endogenously chosen correlation of returns on assets held by banks. The limited liability of banks and the presence of a negative externality of one bank’s failure on the health of other banks give rise to a systemic risk-shifting incentive where all banks undertake correlated investments, thereby increasing economy-wide aggregate risk. Regulatory mechanisms such as bank closure policy and capital adequacy requirements that are commonly based only on a bank’s own risk fail to mitigate aggregate risk-shifting incentives, and can, in fact, accentuate systemic risk. Prudential regulation is shown to operate at a collective level, regulating each bank as a function of both its joint (correlated) risk with other banks as well as its individual (bank-specific) risk.     

Rethinking bank shareholder equity: The case of Deutsche Bank

We introduce and apply an innovative accounting approach to analyse the equity position of a European systemically important financial institution, Deutsche Bank, between 2001 and 2015. According to our findings, the actual contribution by shareholders to bank equity capital was limited, while shareholder payout policies, including share buybacks and trading on its own shares, were both material. These findings raise concerns on the actual capacity by shareholder equity to assure protection against (residual) risk and loss absorption. Customer and investor protections appear to lay with bank entity equity dynamics. These findings have implications for bank financial sustainability and resilience, company capital maintenance, and regulatory capital requirements. Further developments based upon this innovative methodology may improve on existing prudential and accounting regulations.     

Deposit interest rates, asset risk and bank failure in Croatia

Financial deregulation, while beneficial in the long-term, seems to be linked to instability. Intense competition for deposits appears to be an ingredient in instability. We examine the aftermath of deregulation in Croatia, which included rapid growth of both deposits and deposit interest rates, followed by numerous bank failures.

Using panel regression techniques, we find evidence of “market-stealing” via high deposit interest rates. We connect high deposit interest rates to bank failure using logit models. High deposit interest rates were a reliable signal of risk-taking. When supervisory capabilities and powers are weak, deposit interest rate regulation may be worth considering.     

Bank runs, welfare and policy implications

This paper studies the welfare implications of various government policies that have been used to prevent bank runs. The benchmark model suggests that a bank run is a business-cycle-state-related phenomenon and it leads to the failure of the risk-sharing mechanism provided by the banking sector. Extensions of the model show that a number of policy instruments, including the suspension of convertibility of deposits, the taxation on short-term deposits, reserve requirement and blanket guarantee, turn out to be inefficient. Instead, I propose that a limited-coverage deposit insurance scheme or capital requirements can be welfare-improving.     

Incentives and financial crises: Microfounded macroprudential regulation

We provide a micro-based rationale for macroprudential capital regulation of financial intermediaries (banks) by developing a model in which bankers can privately undertake a costly effort and reduce the probability of adverse shocks to their asset holdings that force liquidation (deterioration risk). A decline in the fundamental risk of assets ameliorates funding conditions, boosting the banks’ ability to expand their balance sheets. In principle, a higher continuation value would improve incentives to put effort. However, the rise in asset demand and prices also increases the payoff in liquidation, eventually reducing the equilibrium optimal effort. Poor incentives impose socially inefficient liquidation and can be corrected through a regulatory capital requirement. We show that the requirement should be high when fundamental risk is low. Therefore, the model suggests a theoretical foundation for macroprudential regulation and the countercyclical capital buffer of Basel III.     

Failed bank takeovers and financial stability

Current discussion about the design of bank resolution frameworks suggests that the takeover of a failed bank by an incumbent one has two effects on financial stability. First, the incumbent takeover may boost financial stability by providing bankers with incentives to be solvent so as to profit from their competitors’ failure. Second, the incumbent takeover may spoil financial stability by creating “Systemically Important Financial Institutions”. The innovation of this paper is to capture these two effects in a theoretical model. We show that when incumbent bankers are impatient enough (i.e., they have high discount rates), the second effect prevails over the first one. We discuss the implications of this result for the design of bank resolution policies.     

货币政策、银行资本与风险承担

考虑存款准备金率作为我国货币政策的重要工具,本文在D-L-M模型中引入了法定存款准备金,分析了货币政策对银行风险承担的影响,发现货币政策对银行风险承担的影响取决于银行资本状况。接着利用我国14家上市银行的季度数据,采用门限面板回归模型实证分析了货币政策对银行风险承担的影响。实证结果表明紧缩的货币政策对银行风险承担     

Bank Competition and Financial Stability

Under the traditional “competition-fragility” view, more bank competition erodes market power, decreases profit margins, and results in reduced franchise value that encourages bank risk taking. Under the alternative “competition-stability” view, more market power in the loan market may result in higher bank risk as the higher interest rates charged to loan customers make it harder to repay loans, and exacerbate moral hazard and adverse selection problems. The two strands of the literature need not necessarily yield opposing predictions regarding the effects of competition and market power on stability in banking. Even if market power in the loan market results in riskier loan portfolios, the overall risks of banks need not increase if banks protect their franchise values by increasing their equity capital or engaging in other risk-mitigating techniques. We test these theories by regressing measures of loan risk, bank risk, and bank equity capital on several measures of market power, as well as indicators of the business environment, using data for 8,235 banks in 23 developed nations. Our results suggest that—consistent with the traditional “competition-fragility” view—banks with a higher degree of market power also have less overall risk exposure. The data also provides some support for one element of the “competition-stability” view—that market power increases loan portfolio risk. We show that this risk may be offset in part by higher equity capital ratios.

Bank liquidity regulation and the lender of last resort

Banks can make suboptimal liquidity choices and gamble for lender of last resort (LOLR) support. Endogenous bailout rents are driven by the need to preserve bankers' incentives under uncertain net worth. In equilibrium, banks can herd in risk management, choosing suboptimal liquidity when they expect others to do so. Optimal liquidity can be restored by quantitative requirements, but such regulation is costly. An LOLR policy incorporating bank capital information can reduce distorting rents and allow for a more efficient solution, but may only be possible in transparent economies.     

股权结构、金融生态与城市商业银行绩效

本文利用2006-2010年我国城市商业银行的数据及地区金融生态环境数据,以金融生态环境为切入点,对股权结构、金融生态对城市商业银行绩效的影响进行实证分析。研究结果发现:城市商业银行的第一大股东国有性质、控制能力及股权集中度对城市商业银行绩效存在显著的负向影响。但是当分别分析时,第一大股东的国有性质对处于金融生态好的地区的城商行的绩效的影响为负,而对处于差的金融生态的城商行绩效的影响不显著;第一大股东的国有性质对大规模银行绩效的影响为正向,对小规模银行绩效的影响为负,金融生态对大规模银行绩效的影响系数为负,对小规模银行而言系数为正,但是这种影响不显著。     

Bank Consolidation, Internationalization, and Conglomeration: Trends and Implications for Financial Risk

This paper documents trends in bank activity, consolidation, internationalization, and financial firm conglomeration with data on more than 100 countries, and explores the extent to which financial firm risk and systemic risk potential in banking are related to consolidation and conglomeration. The relationship between consolidation, conglomeration and financial risk is documented using financial data on the largest 500 financial firms worldwide and on large banks in about 90 countries. We find that (a) large conglomerate firms did not exhibit levels of risk‐taking lower than smaller and specialized firms in 1995, while they exhibited higher levels of risk‐taking in 2000; (b) highly concentrated banking systems exhibited levels of systemic risk potential higher than less concentrated systems during the 1993–2000 period, and this relationship has strengthened during the 1997–2000 period. We outline research directions aimed at explaining why bank consolidation and conglomeration may not necessarily yield either safer financial firms or more resilient banking systems.     

The marketability of bank assets, managerial rents and banking stability

Financial innovation and greater information availability have increased the tradability of bank assets and have reduced banks’ dependence on individual bank managers. We show that this can have two opposing consequences for banking stability. First, the hold-up problem between bank managers and shareholders becomes less severe. Consequently, banks’ capital structure needs to be less concerned with disciplining the management. Deposits – the most effective disciplining device – can be reduced, increasing banks’ resilience to adverse return shocks. However, limiting the hold-up problem also diminishes bank managers’ rents, reducing their incentives to properly monitor and screen borrowers, with adverse implications for asset quality. Thus, the default risk of banks does not necessarily decline. We argue that this delivers a novel explanation for the origin of the recent subprime crisis.     

Guarantees,transparency and the interdependency between sovereign and bank default risk

Bank debt guarantees have traditionally been viewed as costless measures to prevent bank runs. However, as recent experiences in some European countries have demonstrated, guarantees may link the coordination problems of bank and sovereign creditors and induce a functional interdependence between the likelihoods of a government default and bank illiquidity. Employing a global-game approach, we model this link, showing the existence and uniqueness of the joint equilibrium and derive its comparative statics properties. In equilibrium, the guarantee reduces the probability of a bank run, while it increases the probability of a sovereign default. The latter erodes the guarantee’s credibility and thus its effectiveness ex ante. By setting the guarantee optimally, the government balances these two effects in order to minimize expected costs of crises. Our results show that the optimal guarantee has clear-cut welfare gains which are enhanced through policies that promote greater balance sheet transparency.     

Bank dividends,risk, and regulatory regimes

This paper investigates the relation between bank dividends and bank risk over the period 1984–2011, and assesses the existence of risk-taking and risk-shifting in the US commercial banking sector subject to regulatory regime changes. The introduction of PCA in 1992 and TARP in 2008 constitute significant regulatory regime changes, and provide the necessary framework to explore whether regime-dependent risk-shifting or risk-taking is present. We find strong evidence of risk-shifting and risk-taking over the post-PCA regime spanning the period 1992–2008. We interpret this evidence as indication of ineffectiveness of PCA in controlling risk-taking and risk-shifting. The finding of risk-taking just prior to the recent financial crisis suggests that risk-taking may be a factor contributing to this crisis. As risk-taking and risk-shifting are important aspects of bank behavior (Basel Committee on Banking Supervision, 2009), these results are of interest to bank regulators and important to Basel III.     

Bank Competition,Risk, and Subordinated Debt

This paper studies a dynamic model of banking in which banks compete for insured deposits, issue subordinated debt, and invest in either a prudent or a gambling asset. The model allows banks to choose their level of risk after the interest rate on subordinated debt is contracted. We show that requiring banks to issue a small amount of subordinated debt can reduce their gambling incentives. Moreover, when equity capital is more expensive than subordinated debt, adding a subordinated debt requirement to a policy regime that only uses equity capital requirements is Pareto improving.

银行损失、资本缓冲与货币政策效果

基于中国银行业1998-2010年面板数据,本文检验银行的损失对贷款供给的影响,并分析资本缓冲(buffer)和货币政策态势(stance)在这种影响中的作用,以进一步考察货币政策效果。经验结果表明:银行损失会导致贷款供给减少,这种影响在银行资本缓冲较少或货币政策紧缩时更明显,在危机时期这种影响也更明显;当资本缓冲较高时,货币政策紧缩使得贷款增长下降较多;货币政策对维护银行业稳定具有重要的作用。     

Bank governance,regulation and risk taking

This paper conducts the first empirical assessment of theories concerning risk taking by banks, their ownership structures, and national bank regulations. We focus on conflicts between bank managers and owners over risk, and we show that bank risk taking varies positively with the comparative power of shareholders within the corporate governance structure of each bank. Moreover, we show that the relation between bank risk and capital regulations, deposit insurance policies, and restrictions on bank activities depends critically on each bank's ownership structure, such that the actual sign of the marginal effect of regulation on risk varies with ownership concentration. These findings show that the same regulation has different effects on bank risk taking depending on the bank's corporate governance structure.     

Bank loan loss accounting treatments,credit cycles and crash risk

Banks that follow conditional conservatism in their loan loss accounting treatments benefit from a reduction in crash risk. The key discretionary loan loss accounting channels are provisions and allowances. We show that conditional conservatism reduces crash risk of small banks during periods of credit contraction and boom. Interestingly, for large banks, crash risk is not reduced by more conservative accounting even for those with higher levels of opacity. Hence regulation prompting for more conservative bank loan loss accounting does not present a significant opportunity to limit systemic effects arising from abrupt price declines in the stocks of large banks.     

The influence of accounting enforcement on earnings quality of banks: Implications of bank regulation and the global financial crisis

We study the effects of country-level accounting enforcement on earnings quality of banks and whether bank regulation substitutes or complements the effect of accounting enforcement on bank earnings quality. We also examine whether the influence of accounting enforcement on bank earnings quality changed after the global financial crisis. Using a sample of listed banks from 40 countries between 2001 and 2014, and abnormal loan loss provisions (ALLP) as our main proxy for earnings quality, we document a consistent and strong association between accounting enforcement and bank earnings quality. More specifically, an increase in accounting enforcement decreases the level of ALLP and decreases the propensity to manage earnings to avoid losses. Furthermore, we provide empirical evidence that bank regulation complements the effect of accounting enforcement on bank earnings quality. Finally, unlike in the pre-crisis period, we find a positive association between accounting enforcement and income-decreasing ALLP in the post-crisis period, which indicates that stronger accounting enforcement is associated with more conservative earnings and higher loan loss reserves. Overall, our results indicate that accounting enforcement reduces opportunistic earnings management.     

Bank CEO materialism: Risk controls,culture and tail risk

We investigate how the prevalence of materialistic bank CEOs has evolved over time, and how risk management policies, non-CEO executives’ behavior and tail risk vary with CEO materialism. We document that the proportion of banks run by materialistic CEOs increased significantly from 1994 to 2004, that the strength of risk management functions is significantly lower for banks with materialistic CEOs, and that non-CEO executives in banks with materialistic CEOs insider trade more aggressively around government intervention during the financial crisis. Finally, we find that banks with materialistic CEOs have significantly more downside tail risk relative to banks with non-materialistic CEOs.