We propose a new and time-varying optimum currency area (OCA) index for the euro area in assessing the evolution of the OCA properties of the monetary union from an international business cycle perspective. It is derived from the relative importance of symmetric vs. asymmetric shocks that result...

Simple models of monetary policy often imply optimal policy behavior that is considerably more aggressive than what is commonly observed. This paper argues that such counterfactual implications are due to model restrictions and a failure to account for multiplicative parameter uncertainty,...