Shapley proved the existence of an ordinal, symmetric and efficient solution for three-player bargaining problems. Ordinality refers to the covariance of the solution with respect to order-preserving transformations of utilities. The construction of this solution is based on a special feature of...

We identify and investigate the basic `hold-up' problem which arises whenever each party to a contingent 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...

We investigate the role that self-control problems modeled as time-inconsistent, present-biased preferences and a person's awareness of those problems might play in leading people to develop and maintain harmful addictions. Present-biased preferences create a tendency to over-consume addictive...

Most properties of binary relations considered in the decision literature can be expressed as the impossibility of certain ``configurations.'' There exists no condition of this form which would hold for a binary relation on a subset of a finite-dimensional Euclidean space if and only if the...

We characterize a rule in cost spanning tree problems using an additivity property and some basic properties. If the set of possible agents has at least three agents, these basic properties are symmetry and separability. If the set of possible agents has two agents, we must add positivity. In...

In this paper we consider the way in which authorities arise in response to the need for coordination. In a model of local interaction, an authority is understood as a self-enforcing coordination selection structure, where the threat of violence ensures compliance. Such authorities form if...

This paper generalizes previous existence results on unidimensional electoral competition, by extending the traditional two-party electoral game to the case where parties have mixed motivations, in the sense that they are interested in winning the election, but also in the policy implemented...

We consider an alternating offer bargaining model in which the players may agree to call in an arbitrator in case of disagreement. The main message of our study is that the mere presence of an arbitrator - who can only become active with the consent of both parties - in the background of...

We study how social norms and individual rationality in the process of coalition formation sustain a particular form of collective inefficiency, namely excessive entry in the joint production and exploitation of an excludable good. We term this phenomenon the `tragedy of the clubs'. We model...