Inputs in the Production of Early Childhood Human Capital: Evidence from Head Start
利用“启智计划”随机评估数据，发现不同中心对儿童认知的短期因果效应差异很大，全日制服务和家访能提升效果，而高瞻课程、教师学历等投入与效果无关。
This paper uses data from a randomized evaluation of Head Start to answer two questions: (i) How much do short-run causal effects vary across Head Start centers? and (ii) Do observed inputs explain this variation? I find that the cross-center standard deviation of cognitive effects is 0.18 test score standard deviations, which is larger than typical estimates of variation in teacher or school effectiveness. Centers offering full-day service and home visiting are more effective, while centers that draw more children from center-based preschool have smaller effects. Other key inputs, including the High/Scope curriculum, teacher education, and class size are not correlated with Head Start effectiveness.