43 Pages Posted: 7 Aug 2014 Last revised: 15 Apr 2015
Date Written: April 15, 2015
We develop a theory of bank liquidity (cash reserve) requirements. Because cash is both observable and riskless, greater cash holdings improve bank incentives to manage risk in the remaining, non-cash portfolio of risky assets. In a model with a single bank, cash is held voluntarily to stem depositors' incentives to withdraw funds early in response to adverse news. In a model with multiple banks and information externalities, deposit insurance may be optimal, and cash reserve requirements are needed to incentivize prudent behavior by banks. In a model with multiple banks subject to liquidity shocks, an interbank market can emerge as long as the group of banks imposes a cash requirement to prevent free riding on interbank liquidity assistance. Our theory has several implications for the design of liquidity regulation that are absent from existing regulatory initiatives.
Keywords: Liquidity regulation, reserve requirements, bank runs, deposit insurance, moral hazard, risk management
JEL Classification: G21, G28, E58, D82
Suggested Citation: Suggested Citation
Calomiris, Charles W. and Heider, Florian and Hoerova, Marie, A Theory of Bank Liquidity Requirements (April 15, 2015). Columbia Business School Research Paper No. 14-39. Available at SSRN: https://ssrn.com/abstract=2477101
By René Stulz