Monetary Policy, Trend Inflation, and Unemployment Volatility

The literature has long agreed that the DMP model (after Diamond 1982, Mortensen 1982, Pissarides 1985) with search and matching frictions in the labor market can deliver large volatilities in labor market quantities, consistent with empirical data, only if there is at least some wage stickiness. I show, however, that the model can deliver nontrivial volatilities without wage stickiness, as long as it has price dispersion and nonzero long‐run inflation rates. I find that by keeping inflation at a positive rate, monetary policy may be accountable for the large standard deviations observed on labor market variables. In addition, the Shimer (2005) puzzle disappears under monetary policy shocks.