A Theory of Experimenters: Robustness, Randomization, and Balance
A Theory of Experimenters: Robustness, Randomization, and Balance
复制标题
实验者理论：稳健性、随机性和平衡
DOI：
10.1257/aer.20171634
复制
发表时间：
2020
影响因子：
10.7
通讯作者：
E. Snowberg
中科院分区：
文献类型：
--
作者：
A. Banerjee;Sylvain Chassang;Sergio Montero;E. Snowberg
本文研究了模糊厌恶决策者在主观期望性能与稳健性能保证之间进行权衡的实验设计问题。这一框架解释了真实世界实验者对随机化的偏好。它还阐明了随机化是最优的情况：当可用样本量较大且稳健性是一个重要问题时。我们应用我们的模型来阐明重新随机的实践，用于改善治疗组和对照组之间的平衡。我们表明，重新随机化在主观性能和稳健性能保证之间产生了一种权衡。然而，稳健的性能保证随着重新随机次数的增加而下降得非常慢。这表明，适度的重新随机化有益地扩大了主观表现和稳健性之间可接受的妥协集。以固定的平衡分位数为目标比以绝对平衡目标为目标更安全。(JEL C90，D81)
This paper studies the problem of experiment design by an ambiguity-averse decision-maker who trades off subjective expected performance against robust performance guarantees. This framework accounts for real-world experimenters’ preference for randomization. It also clarifies the circumstances in which randomization is optimal: when the available sample size is large and robustness is an important concern. We apply our model to shed light on the practice of rerandomization, used to improve balance across treatment and control groups. We show that rerandomization creates a trade-off between subjective performance and robust performance guarantees. However, robust performance guarantees diminish very slowly with the number of rerandomizations. This suggests that moderate levels of rerandomization usefully expand the set of acceptable compromises between subjective performance and robustness. Targeting a fixed quantile of balance is safer than targeting an absolute balance objective. (JEL C90, D81)