Review of Economic Studies · 2020 · Jacob D. Leshno、Irene Lo
中文摘要
本文为学校选择中的顶端交易循环（TTC）机制构建了一个易于分析的理论框架，用以量化福利并优化政策决策。我们计算了不同优先权结构下TTC与延迟接受（DA）机制的福利，发现优先权的选择对福利的影响可能大于机制的选择。我们求解了参数化经济中使福利最大化的学校质量分布，发现TTC与DA下的最优投资决策可能有很大差异。我们的框架依赖于对TTC分配的一种新颖刻画：为每对学校设定一个临界值。这些临界值对应于竞争均衡中的价格，而学生的优先权则发挥禀赋的作用。我们表明，在连续统模型中，这些临界值可以直接根据偏好与优先权的分布计算得出，并推导出参数化设定下的闭式解和比较静态分析结果。TTC的临界值不仅阐明了优先权在决定TTC分配中的作用，也表明TTC比DA更为复杂。
Abstract
Abstract This article develops a tractable theoretical framework for the Top Trading Cycles (TTC) mechanism for school choice that allows quantifying welfare and optimizing policy decisions. We compute welfare for TTC and Deferred Acceptance (DA) under different priority structures and find that the choice of priorities can have larger welfare implications than the choice of mechanism. We solve for the welfare-maximizing distributions of school quality for parametrized economies and find that optimal investment decisions can be very different under TTC and DA. Our framework relies on a novel characterization of the TTC assignment in terms of a cutoff for each pair of schools. These cutoffs parallel prices in competitive equilibrium, with students’ priorities serving the role of endowments. We show that these cutoffs can be computed directly from the distribution of preferences and priorities in a continuum model and derive closed-form solutions and comparative statics for parameterized settings. The TTC cutoffs not only clarify the role of priorities in determining the TTC assignment but also demonstrate that TTC is more complicated than DA.