Term structure and forward guidance as instruments of monetary policy

This paper studies a simple monetary model with a Ricardian fiscal policy in which equilibria are indeterminate if monetary policy consists solely of a rule for fixing the short-term interest rate. We introduce explicitly into the model the agents’ expectations of inflation which create the indeterminacy and show that there are two types of policies—a term structure rule or a forward guidance rule for the short rate—which lead to determinacy. The first consists in fixing the interest rates on a family of bonds of different maturities as function of realized inflation; the second consists in fixing the short-term interest rate and the expected values of the short-term interest rate for a sequence of periods into the future as a function of realized inflation. If the monetary authority chooses an inflation process that satisfies conditions derived in the paper and applies one of these rules, it anchors agents’ expectations to this process, in the sense that it is the unique inflation process compatible with equilibrium when the interest rates or expected future values of the short rate are those specified by the term structure or forward guidance rule.