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...

Destination countries have been resorting to selective immigration policies to improve migrants' quality. We propose a model that analyzes the effects of selective immigration policies on migrants' quality, measured by their wages at destination. Screening potential migrants on the basis of...

We develop a theoretical model where the existence and intensity of dyadic contacts depend on location. We show that agents tend to interact more with agents that are highly central in the network of social contacts and that are geographically closer. Using a unique geo-coded dataset of...

The aim of this paper is to investigate whether return migrants are more likely to become entrepreneurs than non-migrants. We develop a theoretical search model that puts forward the trade off faced by returnees since overseas migration provides an opportunity for human and physical capital...

Recent theoretical work has examined the spatial distribution of unemployment using the efficiency wage model as the mechanism by which unemployment arises in the urban economy. This paper extends the standard efficiency wage model in order to allow for behavioural substitution between leisure...

We develop a model where the decision to commit a crime in a neighboring area is a positive function of the percentage of same-race individuals residing in that area since they can provide crucial information on crime possibilities. The model then predicts a positive spatial correlation in crime...

We model a South African city during Apartheid (in which both schooling and mobility are restricted on the basis of race) and after Apartheid (in which no restrictions are imposed). We first show that the inequality between blacks and whites decreases when Apartheid laws are removed. Indeed,...

We develop a model where information about jobs is essentially obtained through friends and relatives, i.e. strong and weak ties. Workers commute to a business centre to work and to interact with other people. We find that housing prices increase with the level of social interactions in the city...

The aim of this Paper is to study the impact of the size and the quality of social networks on the probability of finding a job. We first develop a theoretical model in which individuals are embedded within a network of social relationships. Workers can obtain information about jobs either...

In this Paper survey some recent developments in urban labour economic theory. We first present a benchmark model in which firms set efficiency wages to prevent shirking and to compensate workers for commuting. We show that both wages and unemployment depend on commuting costs, and that housing...