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...

We study learning and influence in a setting where agents communicate according to an arbitrary social network and naïvely update their beliefs by repeatedly taking weighted averages of their neighbors' opinions. A focus is on conditions under which beliefs of all agents in large societies...

We analyze delinquent networks of adolescents in the United States. We develop a dynamic network formation model showing who the key player is, i.e. the criminal who once removed generates the highest possible reduction in aggregate crime level. We then structurally estimate our model using data...

Although the linear-in-means model is the workhorse model in empirical work on peer effects, its theoretical properties are understudied. In this study, we develop a social-norm model that provides a micro foundation of the linear-in-means model and investigate its properties. We show that...

We present a model for the dynamics of networks in which edges represent positions in organizations, holders of which are connected to each other when the positions belong to the same organization. Once a vacancy is opened, the new employee can be hired from the current network. In particular,...

We study the social integration of ethnic minority children in the context of an early childhood program conducted in Turkey aimed at preparing 5-year-old native and Syrian refugee children for primary school. We randomly assign children to groups with varying ethnic composition and find that...

We consider a modi¯ed pure public good game characterized by a pre-play negotiation stage, onwhich pairs of players can form binding cooperation commitments. As the introduced mecha-nism only supports pairwise rather than more inclusive commitments, it does not implement thee±cient outcome. We...

Bloggers devote significant time not only producing content for others to read, watch or listen to, but also paying attention to and engaging in interactions with other bloggers. We hope to throw light not only on the factors that gain bloggers significant readership and lively interactions with...

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...

This paper investigates opinion dynamics and social influence in directed communication networks. We study the theoretical properties of a boundedly rational model of opinion formation in which individuals aggregate the information they receive from their neighbors by using weights that are a...