Estimating the Returns to College Quality with Multiple Proxies for Quality
指出仅用一个代理变量衡量大学质量会因测量误差低估其对工资的影响，并比较了四种使用多个代理变量的计量方法，发现大学质量对工资的影响比现有文献估计的更大。
Existing studies of the effects of college quality on wages typically rely on a single proxy variable for college quality. This study questions the wisdom of using a single proxy given that it likely contains substantial measurement error. We consider four econometric approaches to the problem that involve the use of multiple proxies for college quality: factor analysis, instruments variables, a method recently proposed by Lubotsky and Wittenberg, and a GMM estimator. Our estimates suggest that the existing literature understates the wage effects of college quality and illustrate the value of using multiple proxies in this and other similar contexts.