种族与学校质量的误测

中文摘要

在大型城市学区，招收更多白人学生的学校往往拥有更高的绩效评级。我们采用一种利用集中式学校分配机制的工具变量策略来探究这一关系。来自丹佛和纽约市的估计结果表明，学校绩效评级与白人学生入学占比之间的相关性反映的是选择性偏误，而非学校的因果增值效应。事实上，在这两个城市，学校增值效应与白人学生入学占比基本无关。研究表明，简单的回归调整可以得到与种族不相关的学校评级，同时其对增值效应的预测能力不逊于甚至优于相应的未调整指标。(JEL H75, I21, I24, I28, J15)

Abstract

In large urban districts, schools enrolling more White students tend to have higher performance ratings. We use an instrumental variables strategy leveraging centralized school assignment to explore this relationship. Estimates from Denver and New York City suggest that the correlation between school performance ratings and White enrollment shares reflects selection bias rather than causal school value added. In fact, value added in these two cities is essentially unrelated to White enrollment shares. A simple regression adjustment is shown to yield school ratings uncorrelated with race while predicting value added as well as or better than the corresponding unadjusted measures. (JEL H75, I21, I24, I28, J15)