We study the immigration policy that maximizes the welfare of the native population in an economy where the government designs an optimal redistributive welfare system and supplies public goods. We show that when the government can design different tax systems for immigrants and natives, free...

We characterize the optimal sequential choice of monetary policy in economies with either nominal or indexed debt. In a model where nominal debt is the only source of time inconsistency, the Markov-perfect equilibrium policy implies the progressive depletion of the outstanding stock of debt,...

We study how barriers to competition---such as restrictions to business start-up and strict enforcement of covenants or IPR---affect the investment in knowledge capital when contracts are not enforceable. These barriers lower the competition for human capital and reduce the incentive to...

We study a general equilibrium model in which entrepreneurs finance investment with optimal financial contracts. Because of enforceability problems, contracts are constrained efficient. We show that limited enforceability amplifies the impact of technological innovations on aggregate output....