Social interactions are considered pivotal to agglomeration economies. We explore a unique dataset on mobile phone calls to examine how distance and population density shape the structure of social interactions. Exploiting an exogenous change in travel times, we show that distance is highly...

This study reviews and evaluates the intertwined relationship between immigration and religiosity, focusing on the two sides of the Atlantic - Europe and the United States. Based on the existing literature and on a statistical analysis of several data sets (the International Social Survey...

In order to explain the substantial recent increases in obesity rates in the United States, we consider the effect of falling food prices in the context of a model involving endogenous body weight norms and an explicit, empirically grounded description of human metabolism. Unlike previous...

We combine information on social networks with medical records and survey data in order to examine how friends affect one's decision to get vaccinated against the flu. The random assignment of undergraduates to residential halls at a large private university allows us to estimate how peer...

Obesity is significantly more prevalent among non-Hispanic African-American (henceforth "black") women than among non]Hispanic white American (henceforth gwhiteh) women. These differences have persisted without much alteration since the early 1970s, despite substantial increases in the rates of...

A common perception about immigrant assimilation is that association with natives necessarily speeds the process by which immigrants become indistinguishable from natives. Using 2000 Census data, this paper casts doubt on this presumption by examining the effect of an immigrant's marriage to a...

Do generations growing up during recessions have different socio-economic beliefs than generations growing up in good times? We study the relationship between recessions and beliefs by matching macroeconomic shocks during early adulthood with self-reported answers from the General Social Survey....

In the more than 30 years following the all-volunteer force (AVF), the proportion of women serving in the military has increased from 1.8 percent just before the AVF to 14.2 percent in 2008. The majority of women do not stay in the military for a 20-year or longer career; like men, most women...

This paper studies whether conformism behavior affects individual outcomes in crime. We present a social network model of peer effects with ex-ante heterogeneous agents and show how conformism and deterrence affect criminal activities. We then bring the model to the data by using a very detailed...