"Satisfactory calculations of the welfare cost of aggregate consumption uncertainty require a framework that replicates major features of asset prices and returns, such as the high equity premium and low risk-free rate. A Lucas-tree model with rare but large disasters is such a framework. In a baseline simulation, the welfare cost of disaster risk is large -- society would be willing to lower real GDP by about 20% each year to eliminate all disaster risk, including wars. In contrast, the welfare cost from usual economic fluctuations is much smaller, though still important -- corresponding to lowering GDP by around 1.5% each year"--National Bureau of Economic Research web site.

Policy uncertainty can reduce individual welfare when individuals have limited opportunities to mitigate or insure against consumption fluctuations induced by the policy uncertainty. For this reason, policy uncertainty surrounding future Social Security benefits may have important welfare costs. We field an original survey to measure the degree of policy uncertainty in Social Security and to estimate the impact of this uncertainty on individual welfare. On average, our survey respondents expect to receive only about 60 percent of the benefits they are supposed to get under current law. We document the wide variation around the expectation for most respondents and the heterogeneity in the perceived distributions of future benefits across respondents. This uncertainty has real costs. Our central estimates show that on average individuals would be willing to forego around 6 percent of the benefits they are supposed to get under current law to remove the policy uncertainty associated with their future benefits. This translates to a risk premium from policy uncertainty equal to 10 percent of expected benefits.

This title was first published in 2002: This monograph sets out to model a macroeconomy that is inherently unstable because of qualitative - or Keynesian - uncertainty. By modelling a macroeconomic theory, this approach to fixed or sticky prices also investigates the link between uncertainty, sticky prices, and macro-stability - by suggesting that such prices improve economic activity rather than impeding it.

First published in 1998. This work contributes to the discussion of Knight by showing that uncertainty broadens the conception of economic welfare, and that a new cost analysis holds the key to unlocking the Knightian corpus. It develops Knight's suggestion that uncertainty-control costs can be reduced - arguing that the large firm enjoys economic rent from utilizing its dominant vantage point in the market. The author demonstrates that while Knight provides the intellectual stimulus which propelled Chamberlin's thesis of monopolistic competition, Chamberlin uses a very abstract form of uncertainty in his analysis.