What's different among banks?
通过事件研究法分析准备金要求取消的影响，发现银行个体层面存在垄断力量，对理解银行竞争和金融监管有参考价值。
Based on commercial paper being a nearly perfect substitute for certificates of deposits (CDs) and CD reserve requirements creating a higher cost of funds for banks, Fama shows that the banking industry must have some monopoly power relative to other financial institutions. His analysis does not resolve whether this monopoly power is vested in banks collectively, vis-à-vis other financial institutions, or if the monopoly power extends to the level of individual banks. Using an event study framework to examine the elimination of a reserve requirement, we find significant evidence of monopoly power at the level of individual banks.