Correlated bank runs,interbank markets and reserve requirements

This article extends the application of global games of Goldstein and Pauzner (2005) in the banking model of Diamond and Dybvig (1983) to account for correlation in the quality of banks’ long term investment, when banks are linked through cross deposits and there is a central bank. The goal is to study how these elements affect the deposit contract that banks offer to depositors and the ex ante probability of a bank run. We show that the coexistence of a central bank, which determines banks’ reserve requirements, and an interbank market, which redistributes reserves, leads to a smaller probability of a bank run and to fewer inefficient bank runs, relative to the case with no central bank and no interbank market. By adequately choosing the level of reserves to store, the central bank can improve the equilibrium outcome and allow banks to offer a higher interim payment to depositors, relative to the situation with no cross deposits.     

论存款保险制度下的风险防范

存款保险制度是一种金融保障制度。建立存款保险制度有利于降低金融风险,防止挤兑发生及危机扩散。当个别银行出现流动性风险时,存款人因为有了相关的法律制度作保证,不再产生巨大的恐惧心理,能避免发生挤兑风潮。同时,建立存款保险制度有利于保护存款人的利益。在投保银行面临支付危机时提供救助,在投保银行破产倒闭时依法清偿存款人的存款,从而保护了存款人的利益。     

Optimal Financial Crises

Empirical evidence suggests that banking panics are related to the business cycle and are not simply the result of "sunspots." Panics occur when depositors perceive that the returns on bank assets are going to be unusually low. We develop a simple model of this. In this setting, bank runs can be first-best efficient: they allow efficient risk sharing between early and late withdrawing depositors and they allow banks to hold efficient portfolios. However, if costly runs or markets for risky assets are introduced, central bank intervention of the right kind can lead to a Pareto improvement in welfare.     

Bank Time Deposit Rates and Market Discipline in Poland: The Impact of State Ownership and Deposit Insurance Reform

This paper examines the impact of ownership structure and changes in the deposit insurance system on the market for bank time deposits in Poland. In an environment of less restrictive bank supervision and a deposit insurance policy that favored state banks, we find that depositors exacted a price for risk-taking. After a new law increasing insurance coverage for private banks went into effect, however, bank specific variables became less important in explaining differences in deposit interest rates. We report, however, that the three fully guaranteed state banks pay significantly lower rates than private banks. Moreover, other state-owned banks, with the same explicit guarantee as private banks, pay significantly lower rates than private banks, so it appears that depositors treat these state-owned banks as if they have a larger implicit guarantee.     

On the Effects of Deposit Insurance and Observability on Bank Runs: An Experimental Study

We study the effects of deposit insurance and observability of previous actions on the emergence of bank runs by means of a controlled laboratory experiment. We consider three depositors in the line of a bank, who decide between withdrawing or keeping their money deposited. We have three treatments with different levels of deposit insurance which reflect the losses a depositor may incur in the case of a bank run. We find that different levels of deposit insurance and the possibility of observing other depositors’ actions affect the likelihood of bank runs. When decisions are not observable, higher levels of deposit insurance decrease the probability of bank runs. When decisions are observable, this need not to be the case. These results suggest that (i) observability might be considered as a partial substitute of deposit insurance and (ii) the optimal deposit insurance should take into account the degree of observability.     

Deposit Insurance and Depositor Monitoring: Quasi-Experimental Evidence from the Creation of the Federal Deposit Insurance Corporation

The Banking Acts of 1933 and 1935 insured deposits up to $5,000 and limited interest paid by commercial banks. This essay uses a treatment-and-control estimation strategy to determine how those reforms influenced depositors’ reactions to information about banks’ balance sheets by comparing preferred and regular depositors at New York state banks. Before deposit insurance, regular depositors reacted more to information about banks, while preferred depositors reacted less. After, this difference diminished and almost disappeared. This change indicates insurance reduced monitoring, although depositors’ continued response to some information indicates that large, uninsured depositors continued to monitor banks, as the legislation intended.     

Deposit Insurance, Capital Adequacy Requirements and Interest Rate Dynamics

This paper examines the long run interaction among deposit insurance, bank deposit rates and capital adequacy requirements. Using analysis similar to the price discrimination model of Lott and Roberts (1991) we find that a competitive environment among banks would link the spread between insured and uninsured deposit rates to the size of the insurance premium. We also find that banks that choose to operate at the regulatory minimum capital level, would increase asset risk with increased capital requirements if (1) the implicit interest paid to insured and uninsured depositors is equally sensitive to changes in risk and capital adequacy and (2) the insurance premium is independent of the level of risk and capital adequacy. Under the present risk-based premium structure, asset risk has the potential to decline when the regulatory agency raises capital requirements. Finally, we examine the time series behavior of insured and uninsured interest rates to see if it is consistent with our theoretical model. We find that insured and uninsured rates, along with deposit insurance premiums, are cointegrated series as suggested by our model.     

Capital Structure, Agency Problems, and Deposit Insurance in Banking Firms

This paper applies and synthesizes various theories of corporate finance, including capital structure, agency insurance, and regulation, to the case of banking firms and the deposite insurance system. It is argued that a value-maximizing bank would reach its optimal capital structure by minimizing the agency costs of incentive conflicts among stockholders, managers, uninsured depositors, and the deposit insurance agency. Although a regulatory imposed capital requirment may reduce the agency costs inherent in the insurance contact, it cannot produce a universal capital structure that is optimal for all insured banks. The observed capital structure patterns also suggest that banks actively seek an optimal capital structure.     

Financial contagion and depositor monitoring

This paper analyzes market discipline in a many-bank economy where contagion and bank runs interact. We present a model with differently-informed depositors, where those depositors that are more informed have incentives to monitor banks’ investments. It is shown that when banks are undercapitalized, and the probability of success of the risky asset is low, depositors might prefer a contract that is subject to bank runs in the interim period to a contract that allows banks to gamble with their funds and maintain their investment.The results of the paper emphasize the benefits of private monitoring of banks in order to promote market discipline.     

Governance by depositors,bank runs and ambiguity aversion

We investigate the theoretical relationship between ambiguity aversion and the decision to withdraw early from a deposit contract. We first document and define the concepts to illustrate our results. Then we extend the theoretical framework of Gorton (1985) to implement a model of maxmin expected utility to match the ambiguity aversion hypothesis. We observe that the most ambiguous depositors are more likely to mistakenly withdraw their deposits, reducing bank stability and leading to inefficient bank runs. We also show higher ambiguity levels negatively impact bank equity levels.     

Market discipline and bank efficiency

This paper investigates whether depositors and market investors exert disciplinary pressure on bank management in terms of efficiency improvement. We find that banks with more outstanding deposits are more cost-efficient, although little effect is found with respect to profit efficiency. This implies that depositors, the primary providers of funds to banks, likely play an important role in disciplining bank management, at least in terms of enforcing efficient use of inputs. Market discipline has garnered increasing attention as a mechanism to ensure bank soundness. Our results imply that depositors, the largest creditors to banks, may be of primary importance in this mechanism.     

Islamic Banks,Deposit Insurance Reform,and Market Discipline: Evidence from a Natural Framework

Although it has been intensively claimed that Islamic banks are subject to more market discipline, the empirical literature is surprisingly mute on this topic. To fill this gap and to verify the conjecture that Islamic bank depositors are indeed able to monitor and discipline their banks, we use Turkey as a test setting. The theory of market discipline predicts that when excessive risk taking occurs, depositors will ask higher returns on their deposits or withdraw their funds. We look at the effect of the deposit insurance reform in which the dual deposit insurance was revised and all banks were put under the same deposit insurance company in December 2005. This gives us a natural experiment in which the effect of the reform can be compared for the treatment group (i.e., Islamic banks) and control group (i.e., conventional banks). We find that the deposit insurance reform has increased the market discipline in the Turkish Islamic banking sector. This reform may have upset the sensitivities of the religiously inspired depositors, and perhaps more importantly it might have terminated the existing mutual supervision and support among Islamic banks.     

银行信息披露制度与银行系统稳定性研究

建立商业银行信息披露制度是我国金融改革中较重要的一环,一般的认识是信息制度的建立将使金融机构运作更审慎,有利于提高整个金融系统的稳定性;但本文通过博弈模型证明:赋予我国商业银行国家信用与进行信息披露制度之间存在着一定的冲突,目前我国对金融体系的过度保护反而会降低商业银行信息披露的对银行体系稳定性的改进,合适的改革次序应是国家信用在金融机构中的先行退出也即建立一个合适的存款保险制度,其次才是规范的信息披露制度的建立.     

Information Acquisition in Rumor‐Based Bank Runs

We study information acquisition and dynamic withdrawal decisions when a spreading rumor exposes a solvent bank to a run. Uncertainty about the bank's liquidity and potential failure motivates depositors who hear the rumor to acquire additional noisy signals. Depositors with less informative signals may wait before gradually running on the bank, leading to an endogenous aggregate withdrawal speed and bank survival time. Private information acquisition about liquidity can subject solvent‐but‐illiquid banks to runs, and shorten the survival time of failing banks. Public provision of solvency information can mitigate runs by indirectly crowding‐out individual depositors' effort to acquire liquidity information.     

Private deposit insurance,deposit flows,bank lending,and moral hazard

We examine the role of private unlimited deposit insurance as a complement to federal deposit insurance for deposit flows, bank lending, and moral hazard during a crisis. We find that banks whose deposits are federally and privately fully insured obtain more deposits and expand lending, in contrast to banks whose deposits are only federally insured. We also document that privately insured banks remain prudent in the loan origination process during the subprime crisis. Our results offer novel insights into depositor and bank behavior in the presence of multiple deposit insurance schemes with differential design features. They also illustrate how private sector solutions incentivize prudent bank behavior to strengthen the financial safety net.     

A Tale of Two Runs: Depositor Responses to Bank Solvency Risk

We examine heterogeneity in depositor responses to solvency risk using depositor‐level data for a bank that faced two different runs. We find that depositors with loans and bank staff are less likely to run than others during a low‐solvency‐risk shock, but are more likely to run during a high‐solvency‐risk shock. Uninsured depositors are also sensitive to bank solvency. In contrast, depositors with older accounts run less, and those with frequent past transactions run more, irrespective of the underlying risk. Our results show that the fragility of a bank depends on the composition of its deposit base.     

Deposit insurance and subsidized recapitalizations

The 2007–2009 financial crisis saw a vast expansion in deposit insurance guarantees around the world and yet our understanding of the design and consequences of deposit insurance schemes is in its infancy. We provide a new rationale for the provision of deposit insurance. In our model the banking sector exhibits both adverse selection and moral hazard, which implies that the social benefits of bank monitoring must for incentive reasons be shared between depositors and banks. Consequently, socially too few deposits are made in equilibrium. Deposit insurance – or, equivalently, bank recapitalization – corrects this market failure. We find that deposit insurance should be funded not by banks or depositors but out of general taxation. The optimal level of deposit insurance varies inversely with the quality of the banking system. Hence, when the soundness of the financial sector is uncertain, governments should consider supporting deposit insurance schemes and undertaking subsidized recapitalizations.     

Reputational contagion and optimal regulatory forbearance

Existing studies suggest that systemic crises may arise because banks either hold correlated assets, or are connected by interbank lending. This paper shows that common regulation is also a conduit for interbank contagion. One bank's failure may undermine confidence in the banking regulator's competence, and, hence, in other banks chartered by the same regulator. As a result, depositors withdraw funds from otherwise unconnected banks. The optimal regulatory response to this behavior can be privately to exhibit forbearance to a failing bank. We show that regulatory transparency improves confidence ex ante but impedes regulators' ability to stem panics ex post.     

Bank Mergers and Diversification: Implications for Competition Policy

This paper analyses competition and mergers among risk averse banks. We show that the correlation between the shocks to the demand for loans and the shocks to the supply of deposits induces a strategic interdependence between the two sides of the market. We characterise the role of diversification as a motive for bank mergers and analyse the consequences of mergers on loan and deposit rates. When the value of diversification is sufficiently strong, bank mergers generate an increase in the welfare of borrowers and depositors. If depositors have more correlated shocks than borrowers, bank mergers are relatively worse for depositors than for borrowers.     

Banking fragility and liquidity creation: options as a substitute for deposits

Diamond and Rajan (J Finance 55:2431–2465, 2000; Am Econ Rev Papers Proc 91:422–425, 2001a; Carnegie–Rochester Conf Series Public Policy 54:37–71, 2001b; J Pol Econ 109:287–327, 2001c) have shown in a series of papers that it is precisely the fragility of their capital structure which allows banks to create liquidity. This is because the threat of runs by depositors forces bankers to extract full repayment on otherwise illiquid assets. This result has important implications for financial regulation, such as for capital requirements and deposit insurance. This note shows that put options held by bank owners dominate deposit financing in that they also discipline bankers but do not give rise to inefficient runs. Fragility is thus not necessary for liquidity creation in the Diamond–Rajan framework. This paper has substantially benefitted from the comments and suggestions of an anonymous referee.