In standard approaches to monetary policy, interest rate rules often lead to indeterminacy. Sophisticated policies, which depend on the history of private actions and can differ on and off the equilibrium path, can eliminate indeterminacy and uniquely implement any desired competitive...

The Ramsey approach to policy analysis finds the best competitive equilibrium given available instruments but is silent about how to get there uniquely. Many ways of specifying monetary policy lead to indeterminacy. Sophisticated policies do not. They depend on the history of past actions and...

The optimal choice of a monetary policy instrument depends on how tight and transparent the available instruments are and on whether policymakers can commit to future policies. Tightness is always desirable; transparency is only if policymakers cannot commit. Interest rates, which can be made...