We determine optimal monetary policy under commitment in a forward-looking New Keynesian model when nominal interest rates are bounded below by zero. The lower bound represents an occasionally binding constraint that causes the model and optimal policy to be nonlinear. A calibration to the U.S....

In a seminal paper, Lucas (1973) provided the theoretical relationship between aggregate demand and real output based on relative price confusion at the individual market level. Ball, Mankiw, and Romer (BMR, 1988) derive the same relation using a New Keynesian framework. Even though both...

Recurring change in a monetary policy function that maps endogenous variables into policy choices alters both the nature and the efficacy of the Taylor principle---the proposition that central banks can stabilize the macroeconomy by raising their interest rate instrument more than one-for-one in...