The Liquidity Trap and U.S. Interest Rates in the 1930s
研究1934-1939年美国隔夜利率为零时，准备金供给如何影响长期利率，发现准备金变化能直接作用于长期利率，即使这些变化不改变市场对未来隔夜利率的预期。
Most current literature assumes that a central bank loses the ability to influence interest rates through variations in reserve supply as soon as overnight rates have been driven to zero. I argue that reserve supply can be directly related to longer-term rates when overnight rates are zero because banks' reserve demand is then defined by the role of cash as an asset free of interest-rate risk. I present evidence that reserve supply affected longer-term interest rates in the U.S. from 1934 through 1939, while overnight rates were at the zero floor, even when the changes in reserve supply reflected factors unlikely to have affected expectations of future overnight rates.