"We analyze optimal monetary policy in an endogenous sticky price model. Similar models with exogenous sticky prices can deliver multiplicity of equilibria. Multiplicity of equilibria is a necessary condition for expectation traps to explain the variation across time and countries of inflation...

This paper proposes a simple framework for analyzing a continuum of monetary policy rules characterized by differing degrees of credibility, in which commitment and discretion become special cases of what we call quasi commitment. The monetary policy authority is assumed to formulate optimal...