We examine friendships and study partnerships among university students over several years. At the aggregate level, connections increase over time, but homophily on gender and ethnicity is relatively constant across time, university residences, and different network layers. At the individual...

This chapter surveys research on social capital. We explore the concepts that motivate the social capital literature, efforts to formally model social capital using economic theory, the econometrics of social capital, and empirical studies of the role of social capital in various socioeconomic...

This paper applies for the first time power index analysis to the famous Krackhardt’s kite social network by imposing a weighted voting game on the given network structure. It compares the results of this analysis, derived by applying the Public Good Index and the Public Value, with the...

We study the incentives that agents have to invest in costly protection against cascading failures in networked systems. Applications include vaccination, computer security and airport security. Agents are connected through a network and can fail either intrinsically or as a result of the...

We study the impact of research collaborations in coauthorship networks on total research output. Through the links in the collaboration network researchers create spillovers not only to their direct coauthors but also to researchers indirectly linked to them. We characterize the interior...

We study the impact of research collaborations in coauthorship networks on research output and how optimal funding can maximize it. Through the links in the collaboration network, researchers create spillovers not only to their direct coauthors but also to researchers indirectly linked to them....

We study the impact of research collaborations in coauthorship networks on research output and how optimal funding can maximize it. Through the links in the collaboration network, researchers create spillovers not only to their direct coauthors but also to researchers indirectly linked to them....

We study the impact of research collaborations in coauthorship networks on research output and how optimal funding can maximize it. Through the links in the collaboration network, researchers create spillovers not only to their direct coauthors but also to researchers indirectly linked to them....

We discuss social network analysis from the perspective of economics. We organize the presentation around the theme of externalities: the effects that one's behavior has on others' welfare. Externalities underlie the interdependencies that make networks interesting to social scientists. We...

The urban space paper is introduced by a brief “report” on the founding of Rome by Romulus; he traced a furrow and thereby defined the urban space. The core of the paper, however, defines the urban space by the dimension of collective decision making expressed in the form of voting games. It...