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...

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...

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...

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...

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 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...

This paper examines the small world hypothesis. The first part of the paper presents empirical evidence on the evolution of a particular world: the world of journal publishing economists during the period 1970-2000. We find that in the 1970's the world of economics was a collection of islands....