Central bank Instruments, Fiscal Policy Regimes, and the Requirements for Equilibrium Determinacy

In this paper we examine the local determinacy conditions for three monetary policy regimes in a business cycle model with staggered price setting. The central bank either controls the nominal interest rate, the money growth rate, or it conducts open market operations and controls the bond-to-money ratio herein. All instruments are set contingent on changes in current inflation. For the first two cases, equilibrium determinacy imposes strong restrictions on the endogenous response to changes in inflation, which depend on whether fiscal policy is Ricardian or non-Ricardian. In the case of open market policy, Ricardian equivalence does not hold and government solvency is guaranteed for finite bond-to- money ratios. The central bank can ensure determinacy by setting the latter not in an extremely reactive way. The equilibrium sequence of real financial wealth then exerts a stabilizing impact on prices and real activity such that equilibrium multiplicity as well as explosiveness is ruled out.