Most existing program evaluation methods examine the average impact of a program. This necessarily overlooks the potential for different program impacts over different parts of the distribution of the variable of interest. To overcome this limitation, we develop a novel methodology for program evaluation which combines stochastic dominance with difference‐in‐differences methods. We use this new method to evaluate the impact of a large decentralization program in Kenya on changes in child nutritional status, where one's primary concern is about sharp adverse (i.e., negative) changes. Using standard difference‐in‐differences regression as a baseline, we find , no statistically or practically significant mean impact. In contrast, our stochastic dominance estimations reveal that project expenditures have had different impacts on different parts of the distribution. In particular, they are associated with less deterioration in children's nutritional status among the worst‐off children, indicating that the program effectively functions as a nutritional safety net.

中文翻译：

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一种随机主导方法进行方案评估，并应用于肯尼亚儿童的营养状况

大多数现有的程序评估方法都会检查程序的平均影响。这必然会忽略对目标变量分布的不同部分产生不同程序影响的可能性。为了克服这一局限性，我们开发了一种新颖的程序评估方法，该方法将随机优势与差异差异方法相结合。我们使用这种新方法来评估肯尼亚大型分权计划对儿童营养状况变化的影响，而儿童的营养状况主要关注的是急剧的不利（即消极）变化。使用标准差异差异回归作为基准，我们发现，没有统计学上或实际上的显着平均影响。相反，我们的随机优势估计表明，项目支出对分配的不同部分产生了不同的影响。尤其是，与贫困状况最严重的儿童相比，它们与儿童营养状况的恶化较少相关，这表明该计划有效地起到了营养安全网的作用。