Research Database

We analyze economies with indivisible commodities. There are two reasons for doing so. First, we extend and provide new insights into sunspot equilibrium theory. Finite competitive economies with perfect markets and convex consumption sets do not allow sunspot equilibria; these same economies with nonconvex consumption sets do, and they have several properties that can never arise in convex environments. Second, we provide a reinterpretation of the employment lotteries used in contract theory and in macroeconomic models with indivisible labor. We show how socially optimal employment lotteries can be decentralized as competitive equilibria once sunspots are introduced.

We examine the validity of one version of the Coase Theorem: In any economy in which property rights are fully allocated, competition will lead to efficient allocations. This version of the theorem implies that the public goods problem can be solved by allocating property rights fully and letting markets do their work. We show that this mechanism is not likely to work well in economies with either pure public goods or global externalities. The reason is that the privatized economy turns out to be highly susceptible to strategic behavior in that the free-rider problem in public goods economies manifests itself as a complementary monopoly problem in the private goods economy. If the public goods or externalities are local in nature, however, market mechanisms are likely to work well.

Our work is related to the recent literature on the foundations of Walrasian equilibrium in that it highlights a relationship among the appropriateness of Walrasian equilibrium as a solution concept, the incentives for strategic play, the aggregate level of complementarities in the economy, and the problem of coordinating economic activity.

A traditional explanation for why sovereign governments repay debts is that they want to keep a good reputation so they can easily borrow more. Bulow and Rogoff have challenged this explanation. They argue that, in complete information models, government borrowing requires direct legal sanctions. We argue that, in incomplete information models with multiple trust relationships, large amounts of government borrowing can be supported by reputation alone.

Intuitively, a patient trader should be able to make his trading partners compete to reveal whatever information is relevant to their transactions with him. This possibility is examined in the context of a model resembling that of Gale (1986). The main result is that, under assumptions having to do with asset structure and spanning, incentive-compatible elicitation of trading partners’ knowledge is feasible.

A classic result in the theory of implicit contract models with asymmetric information is that “underemployment” results if and only if leisure is an inferior good. We introduce household production into the standard implicit contract model and show that we can have underemployment at the same time that leisure is a normal good.