What are the e¤ects of uncertainty shocks on unemployment dynamics? We answer this question by estimating non-linear (Smooth-Transition) VARs with post-WWII U.S. data. The relevance of uncertainty shocks is found to be much larger than that predicted by standard linear VARs in terms of i) magnitude of the reaction of the unemployment rate to such shocks, and ii) contribution to the variance of the prediction errors of unemployment at business cycle frequencies. The ability of di¤erent classes of DSGE models to replicate our results is discussed.

What are the e¤ects of uncertainty shocks on unemployment dynamics? We answer this question by estimating non-linear (Smooth-Transition) VARs with post-WWII U.S. data. The relevance of uncertainty shocks is found to be much larger than that predicted by standard linear VARs in terms of i) magnitude of the reaction of the unemployment rate to such shocks, and ii) contribution to the variance of the prediction errors of unemployment at business cycle frequencies. The ability of di¤erent classes of DSGE models to replicate our results is discussed.

Summary We investigate the macroeconomic consequences of fluctuations in the effectiveness of the labor market matching process with a focus on the Great Recession. We conduct our analysis in the context of an estimated medium‐scale dynamic stochastic general equilibrium model with sticky prices and equilibrium search unemployment that features a shock to the matching efficiency (or mismatch shock). We find that this shock is not important for unemployment fluctuations in normal times. However, it plays a somewhat larger role during the Great Recession when it contributes to raise the actual unemployment rate by around 1.3 percentage points and the natural rate by around 2 percentage points. The mismatch shock is the dominant driver of the natural rate of unemployment and explains part of the recent shift of the Beveridge curve. Copyright © 2016 John Wiley & Sons, Ltd.

We investigate the macroeconomic consequences of fluctuations in the effectiveness of the labor-market matching process with a focus on the Great Recession. We conduct our analysis in the context of an estimated medium-scale DSGE model with sticky prices and equilibrium search unemployment that features a shock to the matching efficiency (or mismatch shock). We find that this shock is not important for unemployment fluctuations in normal times. However, it plays a somewhat larger role during the Great Recession when it contributes to raise the actual unemployment rate by around 1.3 percentage points and the natural rate by around 2 percentage points. The mismatch shock is the dominant driver of the natural rate of unemployment and explains part of the recent shift of the Beveridge curve.