I provide a typology of social capital, breaking it down into seven more fundamental forms of capital: information capital, brokerage capital, coordination and leadership capital, bridging capital, favor capital, reputation capital, and community capital. I discuss how most of these forms of...

We examine the informal exchange of favors in societies such that any two individuals interact too infrequently to sustain exchange, but such that the social pressure of the possible loss of multiple relationships can sustain exchange. Patterns of exchange that are locally enforceable and...

In a model of financial networks that admits both debt and equity interdependencies, we show that financial organizations have incentives to choose excessively risky portfolios, and overly correlate their portfolios with those of their counterparties. We show how optimal regulation depends on...