We show that the welfare of a country's infinitely-lived representative consumer is summarized, to a first order, by total factor productivity (TFP) and by the capital stock per capita. These variables suffice to calculate welfare changes within a country, as well as welfare differences across...

We consider infinite horizon economies populated by a continuum of agents who are subject to idiosyncratic shocks. This framework contains models of saving and capital accumulation with incomplete markets in the spirit of works by Bewley, Aiyagari, and Huggett, and models of entry, exit and...

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...

Policymaking for posterity involves current decisions with distant consequences. Contrary to conventional prescriptions, we conclude that the greater wealth of future generations may strengthen the case for preserving environmental amenities; lower discount rates should be applied to the far...

In welfare theory it is standard to pick the consumption stream that maximizes the welfare of the representative agent. We argue against this position, and show that a benevolent social planner will generally place a greater weight on future consumption than does the representative agent. Our...

How does impatience affect job search? More impatient workers search less intensively and set a lower reservation wage. The effect on the exit rate from unemployment is unclear. In this paper we show that, if agents have exponential time preferences, the reservation wage effect dominates for...

Existing models of open-access resources are applicable to non-storable resources, such as fish. Many open-access resources, however, are used to produce storable goods. Elephants, rhinos, and tigers are three prominent examples. Anticipated future scarcity of these resources will increase...

This essay reviews the family of models that seek to provide aggregate risk based explanations for the empirically observed equity premium. Theories based on non-expected utility preference structures, limited financial market participation, model uncertainty and the small probability of...

This article examines revealed rates of time preference for public goods, using environmental quality as the case study. A nationally representative panel-based sample of 2,914 respondents considered a series of 5 conjoint policy choices, yielding 14,570 decisions. Both the conditional fixed...

This article examines the economic basis for what is termed %u201Crational discounting,%u201D which entails full recognition of policy effects over time and exponential discounting at a riskless rate of return. Policies often cannot be ranked unambiguously in terms of their present or future...