New empirical models of consumer demand that incorporate social preferences, observational learning, word-of-mouth or network effects have the feature that the adoption of others in the reference group - the Òinstalled-baseÓ - has a causal effect on current adoption behavior. Estimation of...

Online applications and services automate communications and transactions between firms and consumers, promising large efficiency gains. However, consumers have been slow to use these online technologies intensively, despite widespread adoption of the internet. Customers frequently undergo a...

Many video ads are designed to go viral, so that the total number of views they receive depends on customers sharing the ads with their friends. This paper explores the relationship between achieving this endogenous reach and the effectiveness of the ad at persuading a consumer to purchase or...

This paper investigates how internet users' perception of control over their personal information affects how likely they are to click on online advertising. The paper uses data from a randomized field experiment that examined the relative effectiveness of personalizing ad copy to mesh with...

In this paper, I develop and estimate a dynamic model of strategic network formation with heterogeneous agents. The main theoretical result is the existence of a unique stationary equilibrium, which characterizes the probability of observing a specific network in the data. As a consequence, the...

We examine the geography of early stage entrepreneurial finance in the context of an internet marketplace for funding new musical artist-entrepreneurs. A large body of research documents that investors in early-stage projects are disproportionately co-located with the entrepreneur. Theory...

We study a model of social learning in networks where agents have heterogeneous preferences, and neighbors tend to have similar preferences---a phenomenon known as homophily. Using this model, we resolve a puzzle in the literature: theoretical models predict that preference diversity helps...

This paper proposes a revealed preference test of network formation models. Specifically, I consider network formation models where agents are (1) strategic, (2) externalities are confined to within an agent’s k-neighborhood, where k can be varied. I show that this model can be tested...

This paper uses a randomized experiment to study whether social networks affect vote choice. In a fiercely contested presidential election in Peru with ten candidates, only 35% of subjects were aware how their friends intended to vote. We compare people who were randomly informed how one of...

This paper studies the competition between firms for influencers in a network. Firms spend effort to convince influencers to recommend their products. The analysis identifies the offensive and defensive roles of spending on influencers. The value of an influencer only depends on the in-degree...