Nearly half of all transactions in the $5 trillion market for manufactured goods in the United States were intermediated by wholesalers in 2012, up from 32 percent in 1992. Seventy percent of this increase is due to the growth of "superstar" firms - the largest one percent of wholesalers....

This paper investigates the role of product upgrades and consumer switching costs in the tying of complementary products. Previous analyses of tying have found that a monopolist of one product cannot increase its profits and reduce social welfare by tying and monopolizing a complementary product...

This paper investigates how the tying of complementary products can be used to preserve and extend monopoly positions. We first show how a firm that is a monopolist of a product in the current period can use tying to preserve its monopoly position in future periods. We then show using related...

Consider two heterogenous populations of agents who, when matched, jointly produce an output, `Y`. For example, teachers and classrooms of students together produce achievement, parents raise children, whose life outcomes vary in adulthood, assembly plant managers and workers produce a certain...

How does an increase in the size of the market due to fertility, immigration, or trade integration, affect welfare and real GDP? We study this question using a model with heterogeneous firms, fixed costs, and monopolistic competition. We decompose the change in welfare into changes in technical...

In this paper, we study ability peer effects in secondary schools in England and identify which segments of the peer ability distribution drive the impact of peer quality on students‟ achievements. To do so, we use census data for four cohorts of pupils taking their age-14 national tests, and...