This paper shows that, with (partial) irreversibility, higher uncertainty reduces the impact effect of demand shocks on investment. Uncertainty increases real option values making firms more cautious when investing or disinvesting. This is confirmed both numerically for a model with a rich mix...

Uncertainty appears to have both a short-run and a long-run component, which we measure using firm and macro implied volatility data from options of 30 days to 10 years duration. We ask what may be driving uncertainty over these different time horizons, finding that oil price volatility is...

We show how real and financial frictions amplify the impact of uncertainty shocks. We build a model with real frictions, and find adding financial frictions roughly doubles the impact of uncertainty shocks. Higher uncertainty alongside financial frictions induces the standard real-options...

We propose uncertainty shocks as a new shock that drives business cycles. First, we demonstrate that microeconomic uncertainty is robustly countercyclical, rising sharply during recessions, particularly during the Great Recession of 2007-2009. Second, we quantify the impact of time-varying...

This review article tries to answer four questions: (i) what are the stylized facts about uncertainty over time; (ii) why does uncertainty vary; (iii) do fluctuations in uncertainty matter; and (iv) did higher uncertainty worsen the Great Recession of 2007-2009? On the first question both macro...

A growing body of evidence suggests that uncertainty is counter cyclical, rising sharply in recessions and falling in booms. But what is the causal relationship between uncertainty and growth? To identify this we construct cross country panel data on stock market levels and volatility as proxies...

We show how real and financial frictions amplify the impact of uncertainty shocks. We build a model with real frictions, and find adding financial frictions roughly doubles the impact of uncertainty shocks. Higher uncertainty alongside financial frictions induces the standard real-options...

We develop a new index of economic policy uncertainty (EPU) based on newspaper coverage frequency. Several types of evidence – including human readings of 12,000 newspaper articles – indicate that our index proxies for movements in policy-related economic uncertainty. Our US index spikes...

We elicit subjective probability distributions from business executives about their own-firm outcomes at a one-year look-ahead horizon. In terms of question design, our key innovation is to let survey respondents freely select support points and probabilities in five-point distributions over...