Individuals derive benefits from their connections, but these may, at the same time, transmit external threats. Individuals therefore invest in security to protect themselves. However, the incentives to invest in security depend on their network exposures. We study the problem of designing a...

The structures of social interaction affect individual behavior and economic performance in important ways. This leads us to ask: does the architecture of social interaction exhibit particular patterns and are these patterns stable over time? We examine interaction among economists by looking at...

In an oligopoly, prior to competing in the market, firms have an opportunity to form pair-wisecollaborative links with other firms. These pair-wise links involve a commitment of resources andlead to lower costs of production of the collaborating firms. The collection of pair-wise linksdefines a...

We examine the incentives of regions in a country to unite or toseparate. We find that smaller regions have greater incentives tounite, relative to larger regions. We show, however, that on thewhole, majority voting on separation and union generates excessiveincentives to separate. This leads us...

In many economic and social contexts, individual players choose their partners and also decide ona mode of behavior in interactions with these partners. This paper develops a simple model toexamine the interaction between partner choice and individual behavior in games of coordination.An...

We develop a model of strategic networks that captures two distinctive features of interfirm collaboration: bilateral agreements and nonexclusive relationships. Our analysis highlights the relationship between market competition, firms' incentives to invest in R&D, and the architecture of...

This paper studies network formation in settings where players are heterogeneous with respect to benefits as well as the costs of forming links. Our results demonstrate that centrality, center-sponsorship and short network diameter are robust features of equilibrium networks. We find that in a...

We develop a model of R&D collaboration in which individual firms carry out in-house research on core activities and undertake bilateral joint projects on non-core activities with other firms. We develop conditions on the profit functions of the firm under which R&D investments in different...

In this paper we test the celebrated `Strength of weak ties' theory of Granovetter (1973). We test two hypotheses on the network structure in a data set of collaborating economists. While we find support for the hypothesis of transitivity of strong ties, we reject the hypothesis that weak ties...