Consider a large market with asymmetric information, in which sellers choose whether to cooperate or deviate and cheat their buyers, and buyers decide whether to re-purchase from different sellers. We model active trade relationships as links in a buyer-seller network and suggest a framework for...

We develop a model of Ponzi schemes with asymmetric information to study Ponzi frauds. A long-lived agent offers to save on behalf of short-lived agents at a higher rate than they can earn themselves. The long-lived agent may genuinely have a superior savings technology, but may be an imposter...

The theory of incomplete contracting is rival to that of complete contracting as a frame of reference to understand contractual relationships. Both approaches rest upon diametrically opposed postulates and lead to very different policy conclusions. From a theoretical viewpoint, scrutiny of the...

Under certain conditions the optimal insurance policy will offer full coverage above a deductible, as Arrow and others have shown long time ago. Interestingly, the same design of insurance policies applies in case of a single loss and ex-ante moral hazard. However, many insurance policies...

We introduce a new class of cooperative games where the worth of a coalition depends on the behavior of other players and on the state of nature as well. We allow for coalitions to form both before and after the resolution of uncertainty, hence agreements must be stable against both types of...

Community enforcement is an important device for sustaining efficiency in some repeated games of cooperation. We investigate cooperation when information about players' reputations spreads to their future partners through links in a social network that connects them. We find that information...

In this paper we show that reputation formation in endogenously formed relationships is a decisive determinant for the existence and performance of credit markets. In theabsence of any third party enforcement of debt repayment the contracting parties succeed in establishing stable bilateral...

We propose a formal way to systematically study the differential effects of exogenous shocks in economic models with heterogeneous agents. Our setting applies to models that can be rephrased as "competition for market shares" in a broad sense. We show that even in presence of any number of...