Learning by Sharing: Monetary Policy and Common Knowledge

A common view states that central bank releases decrease central banks' own information about the economy and are harmful if about inefficient disturbances, such as cost-push shocks. This paper shows how neither is true in a microfounded macroeconomic model in which households and firms learn from central bank releases and the central bank learns from the observation of firm prices. Central bank releases make private sector and central bank expectations closer to common knowledge. This helps transmit dispersed information between the private sector and the central bank. As a result, the release of additional central bank information decreases the central bank's own uncertainty and can be beneficial, irrespective of the efficacy of macroeconomic fluctuations. A calibrated example suggests that the benefits of disclosure are substantial. (JEL D82, D83, D84, E12, E52, E58)