A note on the neo-Fisher effect in the new Keynesian model

Typically, contractionary monetary policy shocks increase the nominal and real rate of interest, which reduces both inflation and output . In contrast, the neo-Fisher effect (NFE) suggests that a transitory but persistent increase in the nominal rate of interest increases inflation in the short run. In a New Keynesian model augmented with several frictions, including the cost channel of monetary policy, real wage rigidity, habit formation in consumption, dampened expectations, and anticipated monetary policy shocks, we derive analytical conditions that give rise to (or avert) the NFE. We show that the NFE can arise due to the interplay between these frictions, and not only when the persistence of the policy shock is large, or when agents are forward-looking, as documented by the existing literature.