We develop new semiparametric methods for estimating treatment effects. We focus on a setting where the outcome distributions may be thick tailed, where treatment effects are small, where sample sizes are large and where assignment is completely random. This setting is of particular interest in...

A policy debate centers around the question how news aggregators such as Google News affect traffic to online news sites. Many publishers view aggregators as substitutes for traditional news consumption while aggregators view themselves as complements because they make news discovery easier. We...

We use U.S. eBay data to investigate how trade is influenced by differences in socioeconomic characteristics, tastes, and trust. States' similarity in cultural characteristics (ethnicity, religious affiliations, and political behavior) is predictive of online trade; cultural similarity similarly...

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....

We study the use of and response to cheap talk by firms and their consumers, focusing on unverifiable promises of charitable donations on eBay. For transactions during March 2005 - May 2006, cheap talk listings have lower sales probabilities but sell at higher prices when they are successful....

'Notice and Choice' has been a mainstay of policies designed to safeguard consumer privacy. This paper investigates distortions in consumer behavior when faced with notice and choice which may limit the ability of consumers to safeguard their privacy using field experiment data from the MIT...

We study the impact of nationalism and interstate frictions on international economic relations by analyzing market reaction to adverse shocks to Sino-Japanese relations in 2005 and 2010. Japanese companies with high China exposure suffer relative declines during each event window; a symmetric...

Quality certification programs help consumers to identify high-quality products or sellers in markets with information asymmetries. Using data from eBay UK's online marketplace, we study how certification's impact on consumer demand varies with market- and seller-level attributes, exploiting...