This paper considers the monetary policymaker's joint problem of model estimation and the design of a policy rule in the face of uncertainty regarding the process of structural change in the economy. Unobserved structural change is modeled through time variation in the natural rates of interest...

This paper investigates the role that imperfect knowledge about the structure of the economy plays in the formation of expectations, macroeconomic dynamics, and the efficient formulation of monetary policy. Economic agents rely on an adaptive learning technology to form expectations and to...