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...

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...

Over the last three decades there has been a dramatic increase in the length of time necessary to publish a paper in a top economics journal. This paper documents the slowdown and notes that a substantial part is due to an increasing tendency of journals to require that papers be extensively...

This paper provides a quick survey of results on the classic SIR model and variants allowing for heterogeneity in contact rates. It notes that calibrating the classic model to data generated by a heterogeneous model can lead to forecasts that are biased in several ways and to understatement of...

A large literature following Hirsch (2005) has proposed citation-based indexes that could be used to rank academics. This paper examines how well several such indexes match labor market outcomes using data on the citation records of young tenured economists at 25 U.S. departments. Variants of...

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....

This paper examines a competitive model of add-on pricing, the practice of advertising low prices for one good in hopes of selling additional products (or a higher quality product) to consumers at a high price at the point of sale. The main conclusion is that add-on pricing softens price...

This paper examines the dynamics of the gender gap in high math achievement over the high school years using data from the American Mathematics Competition. A clear gender gap is already present by 9th grade and the gender gap widens over the high school years. High-achieving students must...

This paper provides a critical review of models of the spread of the coronavirus (SARS-CoV-2) epidemic that have been influential in recent policy decisions. There is tremendous opportunity for social scientists to advance the relevant literature as new and better data becomes available to...

This paper examines a model in which advertisers bid for "sponsored-link" positions on a search engine. The value advertisers derive from each position is endogenized as coming from sales to a population of consumers who make rational inferences about firm qualities and search optimally....