Market Power and Income Taxation

This article analyzes concerns about market power and inequality in a model with multiple sectors, heterogeneous abilities, endogenous labor supply, and nonlinear income taxation. Proportional markups with no profit dissipation have no effect on the economy, and a policy that reduces a nonproportional markup raises (lowers) welfare when it is higher (lower) than a weighted average of other markups. With proportional (partial or full) profit dissipation, proportional markups are equivalent to a downward shift of the distribution of abilities, and the optimal policy rule with nonproportional markups maximizes consumer plus producer surplus despite concerns for distribution and labor supply distortion. (JEL D43, D61, H21, H23, H24, K21, L13, L40)

Optimal Taxation with Behavioral Agents

This paper develops a theory of optimal taxation with behavioral agents. We use a general framework that encompasses a wide range of biases such as misperceptions and internalities. We revisit the three pillars of optimal taxation: Ramsey (linear commodity taxation to raise revenues and redistribute), Pigou (linear commodity taxation to correct externalities), and Mirrlees (nonlinear income taxation). We show how the canonical optimal tax formulas are modified and lead to novel economic insights. We also show how to incorporate nudges in the optimal taxation framework, and jointly characterize optimal taxes and nudges. (JEL D62, D91, H21)

OPTIMAL DYNAMIC NONLINEAR INCOME TAXATION UNDER LOOSE COMMITMENT

This paper examines an infinite-horizon model of nonlinear income taxation in which the probability that the government can commit is high, but not certain. In this “loose commitment” environment, we find that even a little uncertainty over whether the government can commit yields substantial effects on the optimal dynamic nonlinear income tax system. This result holds even though separating taxation remains optimal, as in the case of full commitment. Under an empirically plausible parameterization, our numerical simulations show that high-skilled individuals must be subsidized in the short run, despite the government's redistributive objective, unless the probability of commitment is higher than 98%. Loose commitment also reverses the short-run welfare effects of changes in most of the model's parameters, and yields some counterintuitive outcomes. For example, all individuals are worse off, rather than better off, in the short run when the proportion of high-skilled individuals in the economy increases.