Essays In Banking And Regulation

The broad goal of this dissertation is to further our understanding of the relationship between real and financial sectors of an economy, to identify inefficiencies in financial sector intermediation, and to design financial regulation policies that can address these inefficiencies. The three chapters of this dissertation contribute to specific aspects of the above goal. In the first chapter, I develop a general equilibrium macroeconomic model with a dynamic banking sector in order to characterize optimal size-dependent bank leverage regulation. Bank leverage choices are subject to the risk-return trade-off, and are inefficient due to financial frictions. I show that leverage regulation can generate welfare gains, and that optimal regulation is tighter relative to the benchmark and is bank-size dependent. In particular, optimal regulation is tighter for large banks relative to small banks, and it leads to the following welfare generating effects. First, as small banks take more leverage, they grow faster conditional on survival, leading to a selection effect. Second, small bank failures are less costly while entrants have higher relative efficiency, leading to a cleansing effect. Third, tighter regulation for large banks reduces their failure rate, which generates welfare since large banks are more efficient and costlier to replace, leading to a stabilization effect. The calibrated model rationalizes various steady state moments of the US banking industry, and points towards qualitatively similar but quantitatively tighter leverage regulation relative to the proposition in Basel III accords. In the second chapter, I study the financial contagion problem when banks in order to hedge against idiosyncratic shocks, engage in two-dimensional as opposed to one-dimensional interactions with other banks. To this end, I develop a double-edge interbank network model where banks engage in debt contract and securitization transactions with other banks. I show that the standard intuition of financial contagion does not translate from the one-dimensional case to the two-dimensional case i.e. financial contagion can either weaken or worsen depending on the network and parameter configuration. In particular, I derive parametrization for the case where financial contagion worsens. In the third chapter, we investigate whether countercyclical capital-ratio regulation (CCR) should be implemented strictly as a rule, or whether regulators should have discretion with respect to the timing and magnitude of changes in capital-ratio requirement. Using a simple model we prove the proposition that under information asymmetry, discretionary CCR leads to an increase in policy uncertainty relative to rule-based CCR. We prove a similar proposition for a general finite-horizon economy. Finally, we document that since discretionary CCR enables the regulator to respond to unexpected shocks, a benevolent regulator faces the welfare trade-off while choosing between rule-based and discretionary CCR