Early childhood human capital and development

A growing literature stresses the importance of early childhood human capital. I ask whether variation in early childhood investments can help explain cross-country income differences. I provide new empirical evidence: the adult outcomes of refugees are independent of age at arrival to the United States up to age six, despite dramatic improvements in income and environment upon arrival. A standard model is consistent with this finding if parents but not country are important for early childhood development. This finding limits the mechanisms for generating cross-country early childhood human capital differences. I also provide suggestive evidence on parental inputs.