In an attempt to increase the placement of medical residents to rural hospitals, the Japanese government recently introduced "regional caps" which restrict the total number of residents matched within each region of the country. The government modified the deferred acceptance mechanism...

In most variants of the Hotelling-Downs model of election, it is assumed that voters have concave utility functions. This assumption is arguably justied in issues such as economic policies, but convex utilities are perhaps more appropriate in others such as moral or religious issues. In this...

In costly voting models, voters abstain when a stochastic cost of voting exceeds the benefit from voting. In probabilistic voting models, they always vote for a candidate who generates the highest utility, which is subject to random shocks. We prove an equivalence result: In two-candidate...

Many real matching markets are subject to distributional constraints. These constraints often take the form of restrictions on the numbers of agents on one side of the market matched to certain subsets on the other side. Real-life examples include restrictions on regions in medical matching,...

Real matching markets are subject to constraints. For example, the Japanese government introduced a new medical matching system in 2009 that imposes a "regional cap" in each of its 47 prefectures, which regulates the total number of medical residents who can be employed in each region. Based on...

Distributional constraints are common features in many real matching markets, such as medical residency matching, school admissions, and teacher assignment. We develop a general theory of matching mechanisms under distributional constraints. We identify the necessary and sufficient condition on...