This paper derives the properties of the discount rate that should be applied to a public-sector project when the affected population has heterogeneous degrees of impatience. We show that, for any distribution of discount rates, the social discount rate has the following properties: it decreases...

In this paper, we show that behavioral features can be obtained at a group level when the individuals of the group are heterogeneous enough. Starting from a standard model of Pareto optimal allocations, with expected utility maximizers and exponential discounting, but allowing for heterogeneity...

We address the problem of a social planner who, as in Weitzman (2001), gathers data on experts' discount rates and wants to infer the socially efficient consumption discount rate. We propose an 'equilibrium approach' and we analyse the expression and the properties of the resulting 'equilibrium...