The Ramsey model of fiscal policy implies that taxes should be smooth in the sense of having small variances. In contrast, empirical labour tax processes are smooth in the sense of being random walks; they provide prima facie evidence for incomplete government insurance. This paper considers whether private government information might lie behind such incomplete insurance. It shows that optimal incentive compatible policies exhibit limited use of state contingent debt and greater persistence in taxes and debt, and it argues that they are better approximations to empirical fiscal policies than those implied by the Ramsey model. The paper also establishes that optimal incentive compatible allocations converge to allocations such that the government's incentive compatibility constraint no longer binds. Generally, these limiting allocations are ones in which the government is maximally indebted. Their credibility and the interaction of incentive compatibility and credibility is briefly discussed. Copyright The Review of Economic Studies Limited, 2004.

The Ramsey model of fiscal policy implies that taxes should be smooth in the sense of having small variances. In contrast, empirical labour tax processes are smooth in the sense of being random walks; they provide prima facie evidence for incomplete government insurance. This paper considers whether private government information might lie behind such incomplete insurance. It shows that optimal incentive compatible policies exhibit limited use of state contingent debt and greater persistence in taxes and debt, and it argues that they are better approximations to empirical fiscal policies than those implied by the Ramsey model. The paper also establishes that optimal incentive compatible allocations converge to allocations such that the government's incentive compatibility constraint no longer binds. Generally, these limiting allocations are ones in which the government is maximally indebted. Their credibility and the interaction of incentive compatibility and credibility is briefly discussed.

Discrete location, occupation, skill, and hours choices of workers underpin their incomes. This paper analyzes the optimal taxation of discrete income‐generating choice. It derives optimal tax equations and Pareto test inequalities for mixed logit choice environments that can accommodate discrete and unstructured choice sets, rich preference heterogeneity, and complex aggregate cross‐substitution patterns between choices. These equations explicitly connect optimal taxes to societal redistributive goals and private substitution behavior, with the latter encoded as a substitution matrix that describes cross‐sensitivities of choice distributions to tax‐induced utility variation. In repeated mixed logit settings, the substitution matrix is exactly the Markov matrix of shock‐induced agent transitions across choices. We describe implications of this equivalence for evaluation of prevailing tax designs and the structural estimation of optimal policy mixed logit models. We apply our results to two salient examples: spatial taxation and taxation of couples.

We use a firm-CEO assignment framework to model the market for CEO effective labor. In the model’s equilibrium, more talented CEOs match with and supply more effort to larger firms. Taxation of CEO incomes affects the equilibrium pricing of CEO effective labor and, hence, spills over and affects firm profits. Absent the ability to tax profits or a direct concern for firm owners, a standard prescription for high marginal income taxes emerges. However, given such an ability or concern, the optimal marginal tax rates are much lower.

We study dynamic optimal taxation in a class of economies with private information. Optimal allocations in these environments are complicated and history-dependent. Yet, we show that they can be implemented as competitive equilibria in market economies supplemented with simple tax systems. The market structure in these economies is similar to that in Bewley (1986); agents supply labour and trade risk-free claims to future consumption, subject to a budget constraint and a debt limit. Optimal taxes are conditioned only on two observable characteristics—an agent's accumulated stock of claims, or wealth, and her current labour income. We show that optimal taxes are generally non-linear and non-separable in these variables and relate the structure of marginal wealth and income taxation to the properties of agent preferences.

We develop a recursive dual method for solving dynamic economic problems. The method uses a Lagrangian to pair a dynamic recursive economic problem with a dual problem. We show that such dual problems can be recursively decomposed with costates (i.e., Lagrange multipliers on laws of motion) functioning as state variables. In dynamic contracting and policy settings, the method often replaces an endogenous state space of forward†looking utilities with an exogenously given state space of costates. We provide a principle of optimality for dual problems and give conditions under which the dual Bellman operator is a contraction with the optimal dual value function its unique fixed point. We relate economic problems to their duals, address computational issues, and give examples.

This paper considers the normative implications of technical change for tax policy design. A task-to-talent assignment model of the labor market is embedded into an optimal tax problem. Technical change modifies equilibrium wage growth across talents and the substitutability of talents across tasks. The overall optimal policy response is to reduce marginal income taxes on low to middle incomes, while raising those on middle to high incomes. The reform favors those in the middle of the income distribution, reducing their average taxes while lowering transfers to those at the bottom.