There is a wealth of research in psychology demonstrating that agents process information with the aid of categories. In this paper we study this phenomenon in two parts. First, we build a model of how experiences are sorted into categories and how categorization affects decision making. Second,...

We examine friendships and study partnerships among university students over several years. At the aggregate level, connections increase over time, but homophily on gender and ethnicity is relatively constant across time, university residences, and different network layers. At the individual...

This paper shows that the informativeness principle, as originally formulated by Holmstrom (1979), does not hold if the first-order approach is invalid. We introduce a "generalized informativeness principle" that takes into account non-local incentive constraints and holds generically, even...

The informativeness principle demonstrates qualitative benefits to increasing signal precision. However, it is difficult to quantify these benefits -- and compare them against the costs of precision -- since we typically cannot solve for the optimal contract and analyze how it changes with...