The Effects of Monetary Policy “News” and “Surprises”
在新凯恩斯模型中区分了货币政策的预期（新闻）和非预期（意外）冲击，发现预期冲击对产出的影响更大、更持久，而传统估计混淆了这两种效应。
There is substantial agreement in the monetary policy literature over the effects of exogenous monetary policy shocks. The shocks that are investigated, however, almost exclusively represent unanticipated changes in policy, which surprise the private sector and which are typically found to have a delayed and sluggish effect on output. In this paper, we estimate a New Keynesian model that incorporates news about future policies to try to disentangle the anticipated and unanticipated components of policy shocks. The paper shows that the conventional estimates confound two distinct effects on output: an effect due to unanticipated or “surprise” shocks, which is smaller and more short‐lived than the response usually obtained in the literature, and a large, delayed, and persistent effect due to anticipated policy shocks or “news.” News shocks play a larger role in influencing the business cycle than unanticipated policy shocks, although the overall fraction of economic fluctuations that can be attributed to monetary policy remains limited.