We examine friendships and study partnerships among university students over several years. At the aggregate level, connections increase over time, but homophily on gender and ethnicity is relatively constant across time, university residences, and different network layers. At the individual...

We study the relationship between Hispanic employment and location-specific measures of the distribution of jobs. We find that it is only the local density of jobs held by Hispanics that matters for Hispanic employment, that measures of local job density defined for Hispanic poor English...

This research explores social networks and their relationship to access to health care among adult Mexican-Americans. We use data from the Medical Expenditure Panel Survey (MEPS) linked to data from the 2000 U.S. Census and other data sources. We analyze multiple measures of access to health...

We study the relationship between ethnicity, occupational choice, and entrepreneurship. Immigrant groups in the United States cluster in specific business sectors. For example, Koreans are 34 times more likely than other immigrants to operate dry cleaners, and Gujarati-speaking Indians are 108...

Recently collected data show that, within any manufacturing industry, vertically integrated firms tend to have larger, higher productivity plants, account for the bulk of sales, and also sell externally most of the inputs they produce. In a weak contracting environment characteristic of...

We model social media as collections of users producing and consuming content. Users value consuming content, but doing so uses up their scarce attention, and hence they prefer content produced by more able users. Users also value receiving attention, creating the incentive to attract an...

Using newly validated data on geographic migration networks, we study how labor demand shocks in the United States propagate across the border with Mexico. We show that the large exogenous decline in US employment brought about by the Great Recession affected demographic and economic outcomes in...

We analyze the diffusion of rival information in a social network. In our model, rational agents can share information sequentially, unconstrained by an exogenous protocol or timing. We show how to compute the set of eventually informed agents for any network, and show that it is essentially...

We present a model of online content sharing where agents sequentially observe an article and must decide whether to share it with others. The article may contain misinformation, but at a cost, agents can fact-check it to determine whether its content is entirely accurate. While agents derive...

An information cascade is a situation in which an agent who observes others chooses the same action irrespective of the value of the agent's private information signal. Theoretical models have found that cascades result in poor information aggregation, inaccurate decisions, and fragility of mass...