In this study, we use an industrial-organization model of the banking industry with money creation to examine the effect of conventional and unconventional monetary policy on the money stock. We consider quantitative monetary easing, qualitative monetary easing, and a negative interest rate on excess reserve balances as unconventional monetary policy. Our main findings are as follows. First, under a plausible setting of the parameters, the model with money creation supports the liquidity puzzle, in which tight monetary policy increases the money stock. The greater the number of banks, the stronger the effect. Second, quantitative monetary easing has no impact on money stocks, loans, deposits and bank holding assets other than government bonds. Third, the effect of qualitative monetary easing is ambiguous, but when the number of banks is sufficiently large, the effect is almost the same as the interest rate on reserves. Fourth, the effect of negative interest rate policy is quite complex.

中文翻译：

---

传统和非常规货币政策的产业组织方法

在本研究中，我们使用具有货币创造的银行业的产业组织模型来检验常规和非常规货币政策对货币存量的影响。我们将量化货币宽松、定性货币宽松和超额准备金余额负利率视为非常规货币政策。我们的主要发现如下。首先，在合理的参数设置下，货币创造模型支持流动性难题，即紧缩的货币政策增加了货币存量。银行数量越多，效果越强。其次，量化宽松对货币存量、贷款、存款和政府债券以外的银行持有资产没有影响。三是定性货币宽松效果不明确，但当银行数量足够多时，其效果几乎与准备金利率相同。第四，负利率政策的效果相当复杂。