Cooperativeness among genetically unrelated humans remains a major puzzle in the social sciences. We explore the causal impact of physical distance on willingness to help. In a field setting, participants decide about supporting local refugees at the dispense of money to themselves. We vary...

Obtaining the routing distance between two addresses should not be a hassle in the current state of technology. This is unfortunately more complicated than it first seems. Recently, several Stata commands have been implemented for this purpose (traveltime, traveltime3, mqtime, osrmtime), but...

This paper uses panel data to assess the relative importance of social networks and geographic proximity to micro, small, and medium enterprises in Viet Nam. The results suggest that a larger social network, and hiring employees mainly through social networks, are both correlated with higher...

This paper analyzes the world web of mergers and acquisitions (M&As) using a complex network approach. We use data of M&As to build a temporal sequence of binary and weighted-directed networks, for the period 1995-2010 and 224 countries. We study different geographical and temporal aspects of...

Recent work suggests the patterns of international trade may be distorted because of information frictions. Little is known, however, about how advancements in information communication technology (ICT) affect trade patterns. The goal of our paper is to analyze how and why the adoption of such...

This paper examines the effects of hospital closures on geographical access by potential patients, using data from four southeastern U.S. states. Using optimization models designed to minimize the adverse effects of hospital closures, extensive computations are performed and the results are...

We review and interpret the main theoretical developments in the gravity literature from its very early, a-theoretical applications to the latest structural contributions. We also discuss challenges and implement methods to estimate empirical gravity equations. We finish with a presentation and...