This article explores subjects in optimal income taxation characterized by recent research interest, practical importance in light of concerns about inequality, potential for misunderstanding, and prospects for advancement. Throughout, the analysis highlights paths for further investigation....

We study optimal monetary policy in a general equilibrium economy with heterogeneous agents and nominal rigidities. Households differ in type-specific, state-contingent labor productivity and initial firm ownership, yet markets are complete. The fiscal authority has access to a linear tax...

This essay discusses some things we have learned about markets, in the process of designing marketplaces to fix market failures. To work well, marketplaces have to provide thickness, i.e. they need to attract a large enough proportion of the potential participants in the market; they have to...

We consider the optimal policy problem of a benevolent planner, who is uncertain about an individual's true preferences because of inconsistencies in revealed preferences across behavioral frames. We adapt theories of expected utility maximization and ambiguity aversion to characterize the...

Harberger triangles are used to calculate the efficiency costs of taxes, government regulations, monopolistic practices, and various other market distortions. This paper considers the historical development of Harberger triangles, the associated theoretical controversies, and the contribution of...

This is an invited chapter for the forthcoming Volume 4 of the Handbook of Industrial Organization. We focus on markets with frictions, such as transaction costs, asymmetric information, search and matching frictions. We discuss how such frictions affect allocations, favor the emergence of...

We introduce a new theoretical framework to analyze imperfectly competitive financial markets and trade in assets in an international context. We present a two-country macroeconomic model in which agents are risk averse, assets are imperfect substitutes, the number of financial assets is...

The standard revealed-preference approach to welfare economics encounters fundamental difficulties when the act of choosing directly affects welfare through emotions such as guilt, pride, and anxiety. We address this problem by developing an approach that redefines consumption bundles in terms...

Empirical evidence suggests that individuals often evaluate options relative to a reference point, especially seeking to avoid losses. We undertake the first welfare analysis under reference-dependent preferences. We characterize the welfare impact of changes in reference points and prices,...

This paper develops a welfare accounting decomposition that identifies and quantifies the ultimate origins of welfare gains and losses in general economies with heterogeneous individuals and disaggregated production. The decomposition---exclusively based on preferences and technologies---first...