An Analysis of the Literature on International Unconventional Monetary Policy
梳理了国际非常规货币政策的理论与实证文献，发现其能影响资产价格和尾部风险并改善宏观经济，但建议仅在危机或零利率下限时使用。
This paper evaluates the literature on international unconventional monetary policies (UMPs). Introducing market segmentation, limits-to-arbitrage, and time-consistent policy in standard models permits a theoretical role for UMP. Empirical studies provide compelling evidence that UMPs influenced international asset prices and tail risk in the desired manner. Calibrated modeling and vector autoregressive (VAR) exercises imply that these policies also improved macroeconomic outcomes. We assess the recent debate on the empirical evidence and discuss central bank assessments of UMP. Despite qualified successes, we recommend that UMP be reserved for crises and/or when the zero bound constrains conventional monetary policy.