论文标题
两分设计的因果推断
Causal Inference with Bipartite Designs
论文作者
论文摘要
双方实验是因果推断的最新研究对象,在该因素推断中,将治疗应用于一组单位,并在不同的单位上测量了感兴趣的结果。这些实验在两分图单元之间发生强大干扰效应的设置中特别有用。例如,在市场实验中,在卖方级别分配治疗并测量买方级别(或反之亦然)的结果可能会导致因果模型,从而更好地说明了买卖双方之间自然发生的干扰。尽管已证明双方实验可以改善某些环境中因果效应的估计,但必须仔细进行分析,以免引入不必要的偏见。我们利用广义倾向得分文献来表明,我们可以在一组假设集中获得两分实验的因果效应的无偏估计。我们还讨论了具有适当覆盖概率的信心集的构建。我们使用来自两分实验的先前研究中研究的数据集中的两分图来评估这些方法,并通过模拟显示了显着的偏差降低和改善的覆盖范围。
Bipartite experiments are a recent object of study in causal inference, whereby treatment is applied to one set of units and outcomes of interest are measured on a different set of units. These experiments are particularly useful in settings where strong interference effects occur between units of a bipartite graph. In market experiments for example, assigning treatment at the seller-level and measuring outcomes at the buyer-level (or vice-versa) may lead to causal models that better account for the interference that naturally occurs between buyers and sellers. While bipartite experiments have been shown to improve the estimation of causal effects in certain settings, the analysis must be done carefully so as to not introduce unnecessary bias. We leverage the generalized propensity score literature to show that we can obtain unbiased estimates of causal effects for bipartite experiments under a standard set of assumptions. We also discuss the construction of confidence sets with proper coverage probabilities. We evaluate these methods using a bipartite graph from a publicly available dataset studied in previous work on bipartite experiments, showing through simulations a significant bias reduction and improved coverage.