We examine the effects of collateralized borrowing in a realistically parameterized life-cycle portfolio choice problem. We provide basic intuition in a two-period model and then solve a multi-period model computationally. Our analysis provides insights into life-cycle portfolio choice relevant...

We examine the possibility of a Pareto-improving pay-as-you-go social security system, using an ex-ante welfare criterion. Our objective is to identify the conditions under which a suitably designed pay-as-you-go social security system is welfare improving, when markets are complete and...

In this paper we present circumstances under which the possibility of high leverage can lead to widespread default and national crises. In models with incomplete markets, default and production, there will almost always be a mismatch between firm output across states of nature and asset...

Although equilibrium allocations in models with incomplete markets are generally not Pareto-efficient, it is often argued that quantitative welfare losses from missing assets are small when time horizons are long and shocks are transitory. In this paper, we use a computational analysis to show...

In this paper we identify conditions under which the introduction of a pay-as-you-go social security system is ex-ante Pareto-improving in a stochastic overlapping generations economy with capital accumulation and land. We argue that these conditions are consistent with many calibrations of the...

In this paper we identify conditions under which the introduction of a pay-as-you-go social security system is ex-ante Pareto-improving in a stochastic overlapping generations economy with capital accumulation and land. We argue that these conditions are consistent with many calibrations of the...

In this paper we examine non-parametric restrictions on counterfactual analysis in a simple dynamic stochastic general equilibrium model. Under the assumption of time-separable expected utility and complete markets all equilibria in this model are stationary, the Arrow-Debreu prices uniquely...