We provide benchmarks to evaluate what is an optimal foreign debt and a maximal foreign debt (debt-max), when risk is explicitly considered. When the actual debt exceeds debt-max, then the economy will default when a bad shock occurs. This paper is an application of the stochastic optimal...

The paper derives the optimal carbon tax in closed-form from an integrated assessment of climate change. The formula shows how carbon, temperature, and economic dynamics quantify the optimal mitigation effort. The model's descriptive power is comparable to numeric models used in policy advising....

Using the framework provided by the asymmetric-information and real-options theories, we examine the impact of uncertainty on firms' decisions and market outcomes. We construct alternative measures of uncertainty based on survey of professional forecasters and our estimation of regression-based...

An important element for the public support of policies is their perceived justice. At the same time most policy choices have uncertain outcomes. We report the results of a first experiment investigating just allocations of resources when some recipients are exposed to uncertainty. Although,...

The argument that policy risk, i.e., uncertainty about monetary and fiscal policy, has been holding back the economic recovery in the U.S. during the Great Recession has a large popular appeal. We analyze the role of policy risk in explaining business cycle fluctuations by using an estimated New...

This paper considers investments in cost-reducing technology in the context of contributions to climate protection. Contributions to mitigating climate change are analyzed in a two-period model where later contributions can be based on better information, but delaying the contribution to the...

Authorities often lack information for efficient regulation of the commons. This paper derives a criterion comparing prices versus tradable quantities in terms of expected welfare, given uncertainty, optimal policy and endogenous cost structure. I show that one cannot determine which regulatory...

Recent theoretical work in the economics of climate change has suggested that climate policy is highly sensitive to "fat-tailed" risks of catastrophic outcomes (Weitzman, 2009b). Such risks are suggested to be an inevitable consequence of scientific uncertainty about the effects of increased...

This paper deals with three aspects of spectacular oil price episodes such as the one witnessed in 2008. First, the concept of temporary explosiveness is proposed as an empirical method for capturing this type of behavior. The application of a recently proposed recursive unit root test shows...