What's the matter with tie-breaking? Improving efficiency in school choice

• 成果类型: Article
• 署名作者: Erdil, Aytek; Ergin, Haluk
• 署名单位: University of Oxford; University of Oxford; Washington University (WUSTL)
• 刊物名称: AMERICAN ECONOMIC REVIEW
• ISSN/ISSBN: 0002-8282
• DOI: 10.1257/aer.98.3.669
• 发表日期: 2008
• 页码: 669-689
• 关键词: design; allocation; mechanisms; STABILITY; MARKET

摘要

In several school choice districts in the United States, the student proposing deferred acceptance algorithm is applied after indifferences in priority orders are broken in some exogenous way. Although such a tie-breaking procedure preserves stability, it adversely affects the welfare of the students since it introduces artificial stability constraints. Our main finding is a polynomial-time algorithm for the computation of a student-optimal stable matching when priorities are weak. The idea behind our construction relies on a new notion which we call a stable improvement cycle. We also investigate the strategic properties of the student-optimal stable mechanism.