Preference profiles for efficiency, fairness, and consistency in school choice problems

We study the school choice problem in which a school district assigns school seats to students. There has been a long debate over the three best-known rules for this problem: the deferred acceptance rule (DA), the top-trading cycles rule (TTC), and the immediate acceptance rule (IA). We evaluate these rules by investigating how often they satisfy three central requirements, efficiency, fairness, and consistency. We compare the restricted domains of students’ preferences on which each rule satisfies these requirements. From the containment relations between them, we show that DA performs better than IA, which itself performs better than TTC in terms of efficiency and fairness. If we consider consistency instead, IA performs better than DA, which itself performs better than TTC.