This paper investigates if the impact of uncertainty shocks on the US economy has changed over time. To this end, we develop an extended Factor Augmented VAR model that simultaneously allows the estimation of a measure of uncertainty and its time-varying impact on a range of variables. We find...

Macroeconomic uncertainty—the conditional volatility of the unforecastable component of a future value of a time series—shows considerable variation in the data. A typical assumption in business cycle models is that production is Cobb-Douglas. Under that assumption, this paper shows there is...