Costly Coasian Contracts

We identify and investigate the basic 'hold-up problem' which arises whenever each party to a contract has to pay some ex-ante cost for the contract to become feasible. We then proceed to show that, under plausible circumstances, a 'contractual solution' to this hold-up problem is not available. This is because a contractual solution to the hold-up problem typically entails writing a 'contract over a contract' which generates a fresh set of ex-ante costs, and hence is associated with a new hold-up problem.Ex-ante contractual costs, hold-up problem, Coase theorem, contracts over contracts, incomplete contracts.

Communication in Dynastic Repeated Games: `Whitewashes' and `Coverups

We ask whether communication can directly substitute for memory in dynastic repeated games in which short lived individuals care about the utility of their offspring who replace them in an infinitely repeated game. Each individual is unable to observe what happens before his entry in the game. Past information is therefore conveyed from one cohort to the next by means of communication. When communication is costless and messages are sent simultaneously, communication mechanisms or protocols exist that sustain the same set of equilibrium payoffs as in the standard repeated game. When communication is costless but sequential, the incentives to `whitewash' the unobservable past history of play become pervasive. These incentives to whitewash can only be countered if some player serves as a `neutral historian' who verifies the truthfulness of others' reports while remaining indifferent in the process. By contrast, when communication is sequential and (lexicographically) costly, all protocols admit only equilibria that sustain stage Nash equilibrium payoffs. We also analyze a centralized communication protocol in which history leaves a `footprint' that can only hidden by the current cohort by a unanimous `coverup'. We show that in this case only weakly renegotiation proof payoffs are sustainable in equilibrium.Dynastic Repeated Games, Communication, Whitewashing, Coverups

Structural stability and robustness to bounded rationality

The introduction of a small amount of bounded rationality into a model sometimes has little effect, and sometimes has a dramatic impact on predicted behavior. We call a model robust to bounded rationality if small deviations from rationality result only in small changes in the equilibrium set. We also say that a model is structurally stable if the equilibrium set (given fully rational agents) varies continuously with the parameter values of the model. Our notions of a model and of rationality are quite broad, allowing us to cover cases in which bounded rationality refers to imperfect optimization, non-rational expectations, or arbitrary behavior by a subset of agents. We show that a model is robust to bounded rationality if and only if it is structurally stable. Thus, we can characterize which models will be robust to bounded rationality and which ones will not, independently of the exact form that bounded rationality takes. In addition, from our characterization it follows that introducing a small amount of bounded rationality will have large effects on predicted outcomes if and only if parameters are near a critical point where the equilibrium set changes in a discontinuous way JEL classification: C69, C79, D51, E19

Transaction Costs and the Robustness of the Coase Theorem

This paper explores the extent to which the presence of ex-ante transaction costs may lead to failures of the Coase Theorem. In particular we identify and investigate the basic `hold-up problem' which arises whenever the parties to a Coasian negotiation have to pay some ex-ante costs for the negotiation to take place. We then show that a `Coasian solution' to this hold-up problem is not available. This is because a Coasian solution to the hold-up problem typically entails a negotiation about the payment of the costs associated with the future negotiation which in turn is associated with a fresh set of ex-ante costs, and hence with a new hold-up problemTransaction Costs, Hold-Up Problem, Coase Theorem, Coasian Negotiation.

Costly Bargaining and Renegotiation - (Now published in Econometrica, 69(4) (March 2001), pp. 377-411.)

We identify the inefficiencies that arise when negotiation between two parties takes place in the presence of transaction costs. First, for some values of these costs it is efficient to reach an agreement but the unique equilibrium outcome is one in which agreement is never reached. Secondly, even when there are equilibria in which an agreement is reached, we find that the model always has an equilibrium in which agreement is never reached, as well as equilibria in which agreement is delayed for an arbitrary length of time. Finally, the only way in which the parties can reach an agreement in equilibrium is by using inefficient punishments for (some of) the opponent's deviations. We argue that this implies that, when the parties are given the opportunity to renegotiate out of these inefficiencies, the only equilibrium outcome which survives is the one in which agreement is never reached, regardless of the value of the transaction costs.Optimal bargaining costs, inefficient bargaining outcomes, renegotiation, imperfect recall

Bounded Rationality and Incomplete Contracts

This paper explores the link between boundedly rational behaviour and incomplete contracts. The bounded rationality of the agents in our world is embodied in a constraint that the contracts they write must be algorithmic in nature. We start with a definition of contract incompleteness that seems both appealing and widely applicable. Our first task is then to show that, by itself, the algorithmic nature of contracts is not enough to generate genuinely incomplete contracts in equilibrium. As in Anderlini and Felli (1994), we call this the Approximation Result. We then consider contractual situations in which the complexity costs of a contract are explicitly taken into accoaunt. We consider a broad (axiomatically defined) class of complexity measures and in this framework we show that incomplete contracts obtain in equilibrium. We also extensively discuss some recent literature directly related to the results reported hereIncomplete contracts, bounded rationality, complexity costs

Should courts always enforce what contracting parties write?

We find an economic rationale for the common sense answer to the question in our title — courts should not always enforce what the contracting parties write. We describe and analyze a contractual environment that allows a role for an active court. An active court can improve on the outcome that the parties would achieve without it. The institutional role of the court is to maximize the parties’ welfare under a veil of ignorance. We study a buyer-seller multiple-widget model with risk-neutral agents, asymmetric information and ex-ante investments. The court must decide when to uphold a contract and when to void it. The parties know their private information at the time of contracting, and this drives a wedge between ex-ante and interim-efficient contracts. In particular, if the court enforces all contracts, pooling obtains in equilibrium. By voiding some contracts the court is able to induce them to separate, and hence improve ex-ante welfare. In some cases, an ambiguous court that voids and upholds both with positive probability may be able to increase welfare even further

Should Courts Always Enforce What Contracting Parties Write?

We find an economic rationale for the common sense answer to the question in our title — courts should not always enforce what the contracting parties write. We describe and analyze a contractual environment that allows a role for an active court. An active court can improve on the outcome that the parties would achieve without it. The institutional role of the court is to maximize the parties’ welfare under a veil of ignorance. We study a buyer-seller multiple-widget model with risk-neutral agents, asymmetric information and ex-ante investments. The court must decide when to uphold a contract and when to void it. The parties know their private information at the time of contracting, and this drives a wedge between ex-ante and interim-efficient contracts. In particular, if the court enforces all contracts, pooling obtains in equilibrium. By voiding some contracts the court is able to induce them to separate, and hence improve ex-ante welfare. In some cases, an ambiguous court that voids and upholds both with positive probability may be able to increase welfare even further.Optimal Courts, Informational Externalities, Ex-Ante Welfare