We study the assignment of objects to people via lotteries. We consider the implementation of solutions that are based only on ordinal preferences over the objects. There are three natural ways of comparing lotteries, each of which corresponds to a different notion of Nash equilibrium. For each...

We study a random assignment problem when each agent has possibly multiple demands on objects. In the case of unitary demands, Bogomolnaia and Moulin (2001) introduce the serial rule and characterize it for three-agent economies. We generalize the model to accommodate the possibility that...

We develop a stylized college admission model to analyze the effects of need-blind admission policy which requires admission decisions to be independent of applicants’ financial needs. We show that the need-blind admission policy enhances needy students’ enrollment if financial aid offers...

We study the problem of assigning objects to a group of agents, when each agent has ordinal preferences over the objects. We focus on probabilistic methods, in particular, the serial rule, introduced by Bogomolnaia and Moulin (2001). Liu and Pycia (2011) show that for each economy with "full...

We consider the problem of selecting the locations of two (identical) public goods on an interval. Each agent has preferences over pairs of locations, which are induced from single-peaked rankings over single locations: each agent compares pairs of locations by comparing the location he ranks...

A mechanism guarantees a certain welfare level to its agents, if each of them can secure that level against unanimously adversarial others. How high can such a guarantee be, and what type of mechanism achieves it? In the n-person probabilistic voting/bargaining model with p deterministic...

Agents partition deterministic outcomes into good or bad. A direct revelation mechanism selects a lottery over outcomes - also interpreted as time-shares. Under such dichotomous preferences, the probability that the lottery outcome be a good one is a canonical utility representation. The...

We consider bilateral matching problems where each person views those on the other side of the market as either acceptable or unacceptable: an acceptable mate is preferred to remaining single, and the latter to an unacceptable mate; all acceptable mates are welfare-wise identical. Copyright...

In this paper we consider a model with multiple jurisdictions where each formed jurisdiction selects a public project from the given uni-dimensional set, equally shares its cost among its members and places the project at the location of its median resident. We examine a cooperative concept of...