I study expertise acquisition in a model of trading under asymmetric information. I propose and implement a method to estimate the ratio of social to private marginal value of expertise. This can be decomposed into three sufficient statistics: traders' average profits, the fraction of bad assets...

We propose a criterion of approximate incentive compatibility, strategy-proofness in the large (SP-L), and argue that it is a useful second-best to exact strategy-proofness (SP) for market design. Conceptually, SP-L requires that an agent who regards a mechanism's “prices” as exogenous to...

Some public goods are provided entirely with private contributions, others with a mixture of public and private funding, and still others are entirely publicly funded. To explain this variation, a model of dual provision is developed that endogenizes public and private funding. Members of the...

We model visibility bias in the social transmission of consumption behavior. When consumption is more salient than non-consumption, people perceive that others are consuming heavily, and infer that future prospects are favorable. This increases aggregate consumption in a positive feedback loop....

The public at large, many policymakers, and some economists hold views of social welfare that attach some importance to factors other than individuals' utilities. This note shows that any such non-individualistic notion of social welfare conflicts with the Pareto principle

We use a simple graphical approach to represent Social Welfare Functions that satisfy Independence of Irrelevant Alternatives and Anonymity. This approach allows us to provide simple and illustrative proofs of May's Theorem, of variants of classic impossibility results, and of a recent result on...

In this paper, we propose a new measure of horizontal equity that overcomes many of the shortcomings of previous proposed measures. Our starting point is the observation that a well-behaved social welfare function need not evaluate global' (vertical equity) differences in after-tax income using...

Attempting to shed light on the optimal size of government, economists have analyzed planning problems that specify a set of feasible taxation-spending policies and a social welfare function. The analysis characterizes the optimal policy choice of a planner who knows the welfare achieved by each...

This paper proposes a new way to evaluate tax reforms, by aggregating losses and gains of different individuals using “generalized social marginal welfare weights.” A tax system is optimal if no budget neutral small reform can increase the weighted sum of (money metric) gains and losses...