Optimal monetary and tariff policy in open economies

This paper investigates the relationship between optimal monetary and tariff policy in open economies. In producer-currency pricing (PCP) case, as in Obstfeld and Rogoff (2002), optimal tariff policy rules are separable from optimal monetary policy rules. Except for PCP case, they are not separable from each other. The increase of tariffs will lead to a more insulated world economy in the sense that both home and foreign pay more attention to their domestic goals respectively. When tariffs are chosen optimally, except for PCP and reference-currency pricing (RCP) cases, optimal monetary policy is inward-looking. We also extend the model to consider gains from cooperation. Except for LCP case, there are gains from cooperation between Home and Foreign monetary policy makers. By comparison, there are gains from cooperation between Home and Foreign tariff policy makers in various cases.