This paper studies whether agents must agglomerate at a single location in a class of models of two-sided interaction. In these models there is an increasing returns effect that favors agglomeration, but also a crowding or market-impact effect that makes agents prefer to be in a market with...

We examine the competition between a group of Internet retailers that operate in an environment where a price search engine plays a dominant role. We show that for some products in this environment, the easy price search makes demand tremendously price-sensitive. Retailers, though, engage in...

This paper develops a new approach to testing for strategic entry deterrence and applies it to the behavior of pharmaceutical incumbents just before they lose patent protection. The approach involves looking at a cross-section of markets and examining whether behavior is nonmonotonic in the size...

This paper examines the labor market for mutual fund managers and managers' responses to the implicit incentives created by their career concerns. We find that managerial turnover is sensitie to a fund's recent performance. Consistent with the hypothesis that fund companies are learning about...

Many industries are geographically concentrated. Many mechanisms that could account for such agglomeration have been proposed. We note that these theories make different predictions about which pairs of industries should be coagglomerated. We discuss the measurement of coagglomeration and use...

Data on sales of memory modules are used to explore several aspects of e-retail demand. There is a strong relationship between e-retail sales to a given state and sales tax rates that apply to purchases from online retailers. This suggests that there is substantial substitution between online...

In this paper we explore cross-sectional differences in the behavior and performance of mutual fund managers. In our simplest regression of a fund's market excess return on characteristics of its manager we find that younger managers earn much higher returns than older managers and that managers...

Over the past decade there has been a decline in the fraction of papers in top economics journals written by economists from the highest-ranked economics departments. This paper documents this fact and uses additional data on publications and citations to assess various potential explanations....

The degree of geographic concentration of individual manufacturing industries in the U.S. has declined only slightly in the last twenty years. At the same time, new plant births, plant expansions, contractions and closures have shifted large quantities of employment across plants, firms, and...

This paper develops a model of evolving standards for academic publishing. It is motivated by the increasing tendency of academic journals to require multiple revisions of articles and by changes in the content of articles. Papers are modeled as varying along two quality dimensions: q and r. The...