Respondent driven sampling (RDS) is a network sampling technique typically employed for hard-to-reach populations (e.g. drug users, men who have sex with men, people with HIV). Similar to snowball sampling, initial seed respondents recruit additional respondents from their network of friends....

This paper provides a way of evaluating a player's contribution to her team and relates her effort to her salaries. We collect data from UEFA Euro 2008 Tournament and construct the passing network of each team. Then we determine the key player in the game while ranking all the other players too....

We compare two leading regional innovation systems (RIS) in East Germany with two RIS in West Germany of about the same size and internal settlement structure. Our analyses show that differences in the performance between the regions cannot easily be related to the structural properties of the...

Using data on team assignment and weekly output for all weavers in an urban Chinese textile firm between April 2003 and March 2004, this paper studies a) how randomly assigned teammates affect an individual worker's behavior under a tournament-style incentive scheme, and b) how such effects...

This paper analyzes the determinants of the choice of location of international students. Building on the documented trends in international migration of students, we develop a small theoretical model allowing to identify the various factors associated to the attraction of migrants as well as...

In this paper we investigate the causal effect of immigration on trade flows, using Italian panel data covering very small geographical units (NUTS-3). Exploiting the very favorable setup offered by Italy's features - the very high number of countries of origin of immigrants ('super-diversity'),...

In this paper, I develop and estimate a dynamic model of strategic network formation with heterogeneous agents. While existing models have multiple equilibria, I prove the existence of a unique stationary equilibrium, which characterizes the likelihood of observing a specific network in the...

We develop and analyze a tractable empirical model for strategic network formation that can be estimated with data from a single network at a single point in time. We model the network formation as a sequential process where in each period a single randomly selected pair of agents has the...

Given shortages in public child care in Germany, this paper asks whether social support with child care and domestic work by spouses, kin and friends can facilitate mothers' return to full-time or part-time positions within the first six years after birth. Using SOEP data from 1993-2009 and...