Abstract: After 2022，the global economy faces huge challenges of recovery and monetary policy divergence In the increasingly open international economic environment，the divergence of monetary policy with European and American countries will inevitably have an impact on the effectiveness of Chinas monetary policy Based on the data from January，2005 to December，2022，this paper combines the doubly robust inverse probability weighting (AIPW) with machine learning to quantitatively study the influence of US monetary policy on the effect of Chinas monetary policy Compared with the traditional econometrics method，the biggest advantage of this method is that it can estimate the difference of the influence of different monetary policy combinations of China and the US on the effect of Chinas monetary policy This paper finds that，first，the US monetary policy has spillover effects on Chinas economy，but its impact is generally lower than that of Chinas monetary policy; there is asymmetry in monetary policy effects，with both the US and Chinas monetary policies having a greater effect when tightened individually than when loosened individually Second，the US monetary policy has a significant impact on the effectiveness of Chinese monetary policy，especially on external variables，such as PPI，exchange rate，import，export，direct investment，foreign exchange reserves However，it has a small impact on internal variables，such as industrial added value and total retail sales of consumer goods Third，From the perspective of transmission channels，under different combinations of US and Chinese monetary policies，the main channels through which US monetary policy spillovers occur vary，necessitating targeted measures to enhance the effectiveness of our countrys monetary policy

Key words: monetary policy divergence, policy spillover effect, policy effectiveness, dynamic policy treatment effect

摘要： 2022年之后全球经济面临着复苏和货币政策分化的巨大挑战。在日益开放的国际经济环境中，与欧美国家的货币政策分化不可避免地会对中国货币政策的有效性产生影响。本文基于2005年1月至2022年12月的数据，将双重稳健的逆概率加权法（AIPW）与机器学习方法相结合，定量研究了中美不同货币政策组合下美国货币政策对中国货币政策效果的影响。相比传统的计量经济学方法，本方法最大的优势是能够估计出中美不同货币政策组合对中国货币政策效果影响的差异性。本文发现，第一，美国货币政策对中国经济具有溢出效应，但是其效果整体低于中国货币政策的影响水平；货币政策效果存在不对称性，中美货币政策单独紧缩的效果均大于各自单独宽松的效果。第二，美国货币政策能够影响中国货币政策的有效性，尤其对生产者价格指数以及汇率、进出口、直接投资、外汇储备等外部经济指标影响较为显著，对工业增加值和社会消费品零售总额等内部变量影响较小。第三，从传导渠道来看，中美不同货币政策组合下美国货币政策溢出的主渠道各不相同，需要有针对性地采取应对措施以提升我国货币政策的有效性。

关键词: 货币政策分化, 政策外溢性, 政策有效性, 动态政策处理效应