Nonlinear Effects of Uncertainty Shocks : State-dependency and Asymmetry

The nonlinear effects of uncertainty shocks on U.S. macroeconomic activity are examined using a smooth transition VAR model in which the dynamic relationship between the variables changes with the level of economic policy uncertainty. We find that the responses of the variables change with the level of uncertainty, and in particular, the sign of the response of the inflation rate reverses. The empirical evidence suggests that the behaviors of the shifts in aggregate demand and aggregate supply functions induced by uncertainty shocks depend on the current uncertainty level.