Nonlinear Class Size Effects on Cognitive and Noncognitive Development of Young Children
利用幼儿园班级人数上限20人的规定，研究发现班级规模对幼儿认知发展有非线性影响，且缩小班级规模对弱势地区儿童的非认知技能也有改善作用。
We estimate the nonlinear impact of class size on student achievement by exploiting regulations that cap class size at 20 students per class in kindergarten. Based on student-level information from a previously unexploited and unique large-scale census survey of kindergarten students, this study provides clear evidence of the nonlinearity of class size effects on development measures. While the effects are largest on cognitive development, class size reductions also improve noncognitive skills for children living in disadvantaged areas. These findings suggest that sizeable class size reductions targeted at disadvantaged areas would achieve better results than a marginal reduction across the board.