“Prices versus quantities” (Weitzman 1974), a hugely influential paper, is widely cited (and taught) in current debates about the best policy to reduce greenhouse gas emissions. The paper’s criterion for ranking policies suggests that technological uncertainty favors taxes over cap and...

Over the last few decades, integrated assessment models (IAM) have provided insight into the relationship between climate change, economy, and climate policies. The limitations of these models in capturing uncertainty in climate parameters, heterogeneity in damages and policies, have given rise...

Anthropogenic greenhouse gas emissions are changing the energy balance of our planet. Various climatic feedbacks make the resulting warming over the next decades and centuries highly uncertain. We quantify how this uncertainty changes the optimal carbon tax in a stochastic dynamic programming...

Time and uncertainty constitute essential ingredients to many of the most challenging resource problems. With respect to the time dimension, agents are generally assumed to have a pure time preference as well as a preference for smoothing consumption over time. With respect to risk, agents are...

The social discount rate crucially determines optimal mitigation policies. This paper examines two shortcomings of the recent debate and the models on climate change assessment. First, removing an implicit assumption of (intertemporal) risk neutrality reduces the growth effect in social...

We model welfare-maximizing policy in an infinite-horizon setting when the probability of a tipping point, the welfare change due to a tipping point, and knowledge about a tipping point's trigger all depend on the policy path. Analytic results demonstrate how optimal policy depends on the...

The paper develops an axiomatic framework for rational decision making. The von Neumann-Morgenstern axioms give rise to a richer risk attitude than that captured in the standard discounted expected utility model. I derive three models that permit a more comprehensive risk evaluation. These...

The precise consequences of climate change remain uncertain. We incorporate damage uncertainty into a joint model of climate and the economy, an integrated assessment model. First, both the science and the integrated assessment community analyze uncertainty by means of sensitivity analysis and...

The paper incorporates qualitative differences of probabilistic beliefs into a rational (or normatively motivated) decision framework. Probabilistic beliefs can range from objective probabilities to pure guesstimates. The decision maker in the present model takes into account his confidence in...