The Informational Effect of Monetary Policy and the Case for Policy Commitment

I study how the informational effect of monetary policy changes the optimal conduct of monetary policy. In my model, the private sector extracts information about unobserved shocks from the central bank's interest rate decisions. The central bank optimally changes the informational effect of the interest rate by committing to a state-contingent policy rule, in which case the Phillips curve becomes endogenous to the central bank's optimization problem. In a dynamic model, the optimal policy rule overshoots the natural-rate shock and gradually responds to the cost-push shock, which makes the interest rate change expected output growth but not expected inflation.