Absorptive Capacity and the Growth and Investment Effects of Regional Transfers: A Regression Discontinuity Design with Heterogeneous Treatment Effects
研究发现欧盟对低收入地区的转移支付中，只有约30%和21%的地区（具备足够人力资本和良好制度）能分别转化为更快的人均收入增长和人均投资，且处理效应的方差远大于均值。
Researchers often estimate average treatment effects of programs without investigating heterogeneity across units. Yet, individuals, firms, regions, or countries vary in their ability to utilize transfers. We analyze Objective 1 transfers of the EU to regions below a certain income level by way of a regression discontinuity design with systematically varying heterogeneous treatment effects. Only about 30 percent and 21 percent of the regions—those with sufficient human capital and good-enough institutions—are able to turn transfers into faster per capita income growth and per capita investment, respectively. In general, the variance of the treatment effect is much bigger than its mean.