Using School Choice Lotteries to Test Measures of School Effectiveness
利用公立学校选择抽签的随机分配，检验增值模型（VAM）预测学校因果效应的准确性，发现多数常用VAM能准确预测学生成绩进步。
Value-added models (VAMs) are increasingly used to measure school effectiveness. Yet, random variation in school attendance is necessary to test the validity of VAMs and to guide the selection of models for measuring causal effects of schools. In this paper, I use random assignment from a public school choice lottery to test the predictive power of VAM specifications. In VAMs with minimal controls and two or more years of prior data, I fail to reject the hypothesis that school effects are unbiased. Overall, many commonly used VAMs are accurate predictors of student achievement gains.