The universally beneficial manipulation conjecture of Campbell and Kelly states that for a social choice rule, if everyone gains as a result of any optimal manipulation, then the rule satisfies universally beneficial manipulation, i.e., everyone gains as a result of any manipulation, optimal or...

The Condorcet rule on the domain of profiles at which there exists a unique Condorcet winner is the unique rule satisfying anonymity, neutrality, and strategy-proofness.

We provide a short proof for the following characterization of the core in housing markets first proved by Ma (1994): the core is the only rule that satisfies strategy-proofness, Pareto efficiency and individual rationality.

In a model with finitely many agents who have single-dipped Euclidean preferences on a disc in the Euclidean plane, a rule assigns to each profile of reported dips a point of the disc. It is proved that any strategy-proof and Pareto optimal rule is dictatorial. This framework models situations...

We prove the following result which is equivalent to the Gibbard–Satterthwaite Theorem: when there are at least 3 alternatives, for any unanimous and strategy-proof social choice function, at any given profile if an individual’s top ranked alternative differs from the social choice, then she...

An alternative is a Condorcet winner if it beats all other alternatives in a pairwise majority vote. A social choice correspondence is a Condorcet extension if it selects the Condorcet winners–and nothing else–whenever a Condorcet winner exists. It is well known that Condorcet extensions are...

We study the assignment of agents to clubs in a frictional market environment. Club entry is endogenous and clubs compete by posting reserve prices in a competing auctions game prior to the agents’ decisions regarding which club to visit. The competing auctions equilibrium is constrained...

We consider methods of electing a fixed number of candidates, greater than one, by approval ballot. We define a representativeness property and a Pareto property and show that these jointly imply manipulability.

This note provides an alternative derivation of the leximin principle using the framework of Harsanyi’s (1953) equi-probability model. We demonstrate that the leximin principle is concluded if and only if the preference ordering of the impartial observer obeys strong monotonicity and complete...

Recent research on the Condorcet Jury Theorem has proven that informative voting (that is, voting according to one’s signal) is not necessarily rational. With two alternatives, rational voting typically leads to the election of the correct alternative, in spite of the fact that not all voters...