Illiquidity, insolvency, and banking regulation

This paper provides a compact framework for banking regulation analysis in the presence of uncertainty between systemic liquidity and solvency shocks. Extending the work by Cao & Illing (2009a, b), it is shown that systemic liquidity shortage arises endogenously as part of the inferior mixed strategy equilibrium. The paper compares dierent traditional regulatory policies which intend to fix the ineciencies, and argues that the co-existence of illiquidity and insolvency problems adds extra cost for banking regulation and makes some schemes that are optimal under pure illiquidity risks (such as liquidity regulation with lender of last resort policy) fail. The regulatory cost can be minimized by combining the advantages of several instruments

Network tomography based on 1-D projections

Network tomography has been regarded as one of the most promising methodologies for performance evaluation and diagnosis of the massive and decentralized Internet. This paper proposes a new estimation approach for solving a class of inverse problems in network tomography, based on marginal distributions of a sequence of one-dimensional linear projections of the observed data. We give a general identifiability result for the proposed method and study the design issue of these one dimensional projections in terms of statistical efficiency. We show that for a simple Gaussian tomography model, there is an optimal set of one-dimensional projections such that the estimator obtained from these projections is asymptotically as efficient as the maximum likelihood estimator based on the joint distribution of the observed data. For practical applications, we carry out simulation studies of the proposed method for two instances of network tomography. The first is for traffic demand tomography using a Gaussian Origin-Destination traffic model with a power relation between its mean and variance, and the second is for network delay tomography where the link delays are to be estimated from the end-to-end path delays. We compare estimators obtained from our method and that obtained from using the joint distribution and other lower dimensional projections, and show that in both cases, the proposed method yields satisfactory results.Comment: Published at http://dx.doi.org/10.1214/074921707000000238 in the IMS Lecture Notes Monograph Series (http://www.imstat.org/publications/lecnotes.htm) by the Institute of Mathematical Statistics (http://www.imstat.org

Endogenous Systemic Liquidity Risk

Traditionally, aggregate liquidity shocks are modelled as exogenous events. Extending our previous work (Cao & Illing, 2007), this paper analyses the adequate policy response to endogenous systemic liquidity risk. We analyse the feedback between lender of last resort policy and incentives of private banks, determining the aggregate amount of liquidity available. We show that imposing minimum liquidity standards for banks ex ante are a crucial requirement for sensible lender of last resort policy. In addition, we analyse the impact of equity requirements and narrow banking, in the sense that banks are required to hold sufficient liquid funds so as to pay out in all contingencies. We show that such a policy is strictly inferior to imposing minimum liquidity standards ex ante combined with lender of last resort policy

Liquidity Shortages and Monetary Policy

The paper models the interaction between risk taking in the financial sector and central bank policy. It shows that in the absence of central bank intervention, the incentive of financial intermediaries to free ride on liquidity in good states may result in excessively low liquidity in bad states. In the prevailing mixed-strategy equilibrium, depositors are worse off than if banks would coordinate on more liquid investment. It is shown that public provision of liquidity improves the allocation, even though it encourages more risk taking (less liquid investment) by private banks