Immigration is having an increasingly important effect on the social insurance system in the United States. On the one hand, eligible legal immigrants have the right to eventually receive pension benefits but also rely on other aspects of the social insurance system such as health care,...

One important feature of tax reforms, in particular corporate tax reforms, is the uncertainty surrounding them. Are they going to be permanent or are they likely to be withdrawn by the subsequent government? The expected duration of the reform is important because it affects households' economic...

Alvarez and Jermann (2000) show that the constrained efficient allocations of endowment economies with imperfect risk sharing due to limited commitment can be decentralized as competitive equilibria with endogenous debt constraints that are not too tight. These are the loosest possible borrowing...