Research Database

In this paper, we consider an environment in which agents’ productivities are private information, potentially multi-dimensional, and follow arbitrary stochastic processes. We allow for arbitrary incentive-compatible and physically feasible tax schemes. We prove that it is typically Pareto optimal to have positive capital taxes. As well, we prove that in any given period, it is Pareto optimal to tax consumption goods at a uniform rate.

One of the long-standing issues in the literature on transfer programs for the U.S. low-income population concerns the high cumulative marginal tax rate on earnings induced by participation in the multiplicity of programs offered by the government. Empirical work on the issue has reached an impasse partly because the analytic solution to the choice problem is intractable and partly because the model requires the estimation of multiple sets of equations with limited dependent variables, an estimation problem which until recently has been computationally infeasible. In this paper we estimate a model of labor supply and multiple program participation using methods of simulation estimation that enable us to solve both problems. The results show asymmetric wage and tax rate effects, with fairly large wage elasticities of labor supply but very inelastic responses to moderate changes in cumulative marginal tax rates, implying that high welfare tax rates do not necessarily induce major reductions in work effort.

How much discretion is it optimal to give the monetary authority in setting its policy? We analyze this mechanism design question in an economy with an agreed-upon social welfare function that depends on the randomly fluctuating state of the economy. The monetary authority has private information about that state. In the model, well-designed rules trade off society’s desire to give the monetary authority flexibility to react to its private information against society’s need to guard against the standard time inconsistency problem arising from the temptation to stimulate the economy with unexpected inflation. We find that the optimal degree of monetary policy discretion is decreasing in the severity of the time inconsistency problem. As this problem becomes sufficiently severe, the optimal degree of discretion is none at all. We also find that, despite the apparent complexity of this dynamic mechanism design problem, society can implement the optimal policy simply by legislating an inflation cap that specifies the highest allowable inflation rate.

This paper examines the optimal debt contract between lenders and a sovereign borrower when the borrower is free to repudiate the debt and when his decision to invest or consume borrowed funds is unobservable. We show that recurrent debt crises are a necessary part of the incentive structure which supports the optimal pattern of lending.

We construct a sequence of pure exchange, stationary OLG economies in which generations have longer and longer life spans and all agents maximize a discounted sum of utilities with a fixed, positive, and common discount rate. Period utility functions and endowment patterns are subject to mild restrictions and within generation heterogeneity is permitted. We show that: (i) Every sequence of equilibrium interest rates converges to the discount rate. (ii) Eventually every nonmonetary steady state is optimal and a monetary steady state will never exist. (iii) For any agent consumption at any fixed age converges to permanent income evaluated using the utility discount rate.