一篇研究倾向得分匹配的综述性、实践性的文章

CaliendoMacro, Kopeinig Sabine. Some practical guidance for the implementation ofpropensity score matching [J]. Journal ofEconomic Surveys, 2008, 22(1), 31–72.

不理解的一些概念，感觉比较别扭，请朋友们指点，谢谢。

Outcomes over common support

Support problems

Balance all covariates

Propensity score is balanced.