Erdil, A. and Ergin, H.

What's the matter with tie-breaking? Improving efficient

American Economic Review

Vol. 98(3) pp. 669-689 (2008)

Abstract: 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.

Author links: Aytek Erdil  

Publisher's Link: http://www.aeaweb.org/articles.php?doi=10.1257/aer.98.3.669