We derive the optimal contributions to global climate policy when countries differ with respect to income level and pollution intensity. Countries' growth rates are determined endogenously, and abatement efficiency is improved by technical progress. We show that country heterogeneity has a...

We study a growth model with two types of agents who are heterogeneous in their degree of family altruism. We prove that every equilibrium path converges to a unique steady state, and study the effect of altruism on the properties of steady-state equilibrium. We show that aggregate income is...

We extend the Lucas' 1988 model introducing two classes of agents with heterogeneous skills, discount factors and initial human capital endowments. We consider two regimes according to the planner's political constraints. In the first regime, that we call meritocracy, the planner faces...

We develop two models of economic growth with exhaustible natural resources and consumers heterogeneous in time preferences. The first model assumes private ownership of natural resources. In the second model, natural resources are commonly owned and the resource extraction rate is chosen by...