Every agent reports his willingness to pay for one unit of a good. A mechanism allocates goods and cost shares to some agents. We characterize the group strategyproof (GSP) mechanisms under two alternative continuity conditions interpreted as tie-breaking rules. With the maximalist rule (MAX) an...

We model a common pool resource game under environmental uncertainty, where individuals in a symmetric group face the dilemma of sharing a common resource. Each player chooses a consumption level and obtains a corresponding share of that resource, but if total consumption exceeds a sustainable...

In the presence of self-interested parties, mechanism designers typically aim to implement some social-choice function in an equilibrium. This paper studies the cost of such equilibrium requirements in terms of communication. While a certain amount of information x needs to be communicated just...

We analyze the problem of aggregating judgments over multiple issues from the perspective of whether aggregate judgments manage to efficiently use all voters' private information. While new in judgment aggregation theory, this perspective is familiar in a different body of literature about...

We consider full implementation in complete-information environments when agents have an arbitrarily small preference for honesty. We offer a condition called separable punishment and show that when it holds and there are at least two agents, any social choice function can be implemented by a...

We consider the problem of dividing a homogeneous divisible good among n players. Each player holds a private non-negative utility function that depends only on the amount of the good that he receives. We define the fair share of a player P to be the average utility that a player could receive...

We offer complete characterizations of the equilibrium outcomes of two prominent agenda voting institutions that are widely used in the democratic world: the amendment, also known as the Anglo-American procedure, and the successive, or equivalently the Euro-Latin procedure. Our axiomatic...

We analyze the problem of a jury that must rank a set of contestants whose socially optimal ranking is common knowledge among jurors who may have friends among the contestants and may, therefore, be biased in their friends' favor. We show a natural mechanism that is finite and complete...

We prove that the structure theorem for rationalizability originally from Weinstein and Yildiz (2007) applies to any finite extensive-form game with perfect recall and suitably rich payoffs. We demonstrate that the ties induced by the extensive form do not change the result of Weinstein and...

We define a generalized state-space model with interactive unawareness and probabilistic beliefs. Such models are desirable for potential applications of asymmetric unawareness. Applying our unawareness belief structures, we show that the common prior assumption is too weak to rule out...