Simple monetary policy rules and exchange rate uncertainty

We analyze the performance and robustness of some common simple rules for monetary policy in a new-Keynesian open economy model under different assumptions about the determination of the exchange rate. Adding the exchange rate to an optimized Taylor rule gives only slight improvements in terms of the volatility of important variables in the economy. Furthermore, although the rules including the exchange rate (and in particular, the real exchange rate) perform slightly better than the Taylor rule on average, they sometimes lead to very poor outcomes. Thus, the Taylor rule seems more robust to model uncertainty in the open economy.