Making just school assignments

• 成果类型: Article
• 署名作者: Morrill, Thayer
• 署名单位: North Carolina State University
• 刊物名称: GAMES AND ECONOMIC BEHAVIOR
• ISSN/ISSBN: 0899-8256
• DOI: 10.1016/j.geb.2015.05.004
• 发表日期: 2015
• 页码: 18-27
• 关键词: Top trading cycles; school choice; assignment

摘要

It is impossible for a mechanism to be strategyproof, Pareto efficient, and eliminate justified envy. However, little is known to what extent a strategyproof and efficient mechanism can limit justified envy. We define an assignment to be unjust if a student i is not assigned to a school a that she prefers to her own assignment, i has higher priority at a than some student j who is assigned to a, and none of the students ranked higher at a than i are dependent on j. We prove that Top Trading Cycles is the unique mechanism that is strategyproof, efficient, and just. This demonstrates that a strictly stronger notion of fairness than justness is either unachievable by a strategyproof and efficient mechanism or it is only achievable by TTC. We extend this characterization to the general case when schools may have arbitrary capacities by introducing the concept of reducibility. (C) 2015 Elsevier Inc. All rights reserved.