Dynamic Matching in School Choice: Efficient Seat Reassignment After Late Cancellations

• 成果类型: Article
• 署名作者: Feigenbaum, Itai; Kanoria, Yash; Lo, Irene; Sethuraman, Jay
• 署名单位: City University of New York (CUNY) System; Lehman College (CUNY); City University of New York (CUNY) System; Columbia University; Stanford University; Columbia University
• 刊物名称: MANAGEMENT SCIENCE
• ISSN/ISSBN: 0025-1909
• DOI: 10.1287/mnsc.2019.3469
• 发表日期: 2020
• 页码: 5341-5361
• 关键词: Dynamic matching; matching markets; school choice; deferred acceptance; tie breaking; cancellations; reassignments

摘要

In the school choice market, where scarce public school seats are assigned to students, a key operational issue is how to reassign seats that are vacated after an initial round of centralized assignment. Practical solutions to the reassignment problem must be simple to implement, truthful, and efficient while also alleviating costly student movement between schools. We propose and axiomatically justify a class of reassignment mechanisms, the permuted lottery deferred acceptance (PLDA) mechanisms. Our mechanisms generalize the commonly used deferred acceptance (DA) school choice mechanism to a two-round setting and retain its desirable incentive and efficiency properties. School choice systems typically run DA with a lottery number assigned to each student to break ties in school priorities. We show that under natural conditions on demand, the second-round tiebreaking lottery can be correlated arbitrarily with that of the first round without affecting allocative welfare and that reversing the lottery order between rounds minimizes reassignment among all PLDA mechanisms. Empirical investigations based on data from New York City high school admissions support our theoretical findings.