We study a multi-dimensional collective decision under incomplete information. Agents have Euclidean preferences and vote by simple majority on each issue (dimension), yielding the coordinate-wise median. Judicious rotations of the orthogonal axes -- the issues that are voted upon -- lead to...

For any linear transformation and two convex closed sets, we provide necessary and sufficient conditions for when the transformation of the intersection of the sets coincides with the intersection of their images. We also identify analogous conditions for non-convex sets, general...

This study explores mechanism design with allocation-based social preferences. Agents' social preferences and private payoffs are all subject to asymmetric information. We assume quasi-linear utility and independent types. We show how the asymmetry of information about agents' social preferences...

This paper considers the problem faced by a political authority that has to design a legislative mechanism that guarantees the selection of policies that are stable, efficient, and inclusive in the sense of strategically protecting minority interests. Experimental studies suggest that some of...

We study decision rules for committees that repeatedly take a binary decision. Committee members are privately informed about their payoffs and monetary transfers are not feasible. In static environments, the only strategy-proof mechanisms are voting rules which are criticized for being...

This paper studies a model of mechanism design with transfers where agents' preferences need not be quasilinear. In such a model, (1) we characterize dominant strategy incentive compatible mechanisms using a monotonicity property; (2) we establish a revenue uniqueness result: for every dominant...

We prove a general possibility result for collective decision problems where individual allocations are one-dimensional, preferences are single-peaked (strictly convex), and feasible allocation profiles cover a closed convex set. Special cases include the celebrated median voter theorem (Black...

When is a mechanism designer justified in only asking for ordinal information about preferences? Simple examples show that, even if the planner's goal (expressed by a social choice correspondence, or SCC) depends only on ordinal information, eliciting cardinal information may help with...

We study a classic mechanism design problem: How to organize trade between two privately informed parties. We characterize an optimal mechanism under selfish preferences and present experimental evidence that, under such a mechanism, a non-negligible fraction of individuals deviates from the...

Many environmental-policy problems are characterized by complexity and uncertainty. Government's choice concerning these policies commonly relies on information provided by a bureaucracy. Environmental bureaucrats often have a political motivation of their own, so they might be tempted to...