论文标题
学习反事实推断的分解代表
Learning Decomposed Representation for Counterfactual Inference
论文作者
论文摘要
观察数据的治疗效应估计中的基本问题是混杂的识别和平衡。以前的大多数方法都通过将所有观察到的预处理变量视为混杂因素,实现了混杂因素的平衡,而忽略了进一步的识别混杂因素和非共鸣者。通常,并非所有观察到的预处理变量都是指指疗法和结果的共同原因的混杂因素,有些变量仅有助于治疗,有些变量仅有助于结果。平衡这些非共鸣者,包括仪器变量和调整变量,将产生额外的偏见来估计治疗效果。通过对观察到的预处理变量,治疗和结果之间的不同因果关系进行建模,我们向1)通过学习混杂因素和非共鸣者的分解代表来识别混杂因素,提出一个协同的学习框架,2)2)与样本重新介绍技术的混杂因素平衡,并同时通过相对的研究来估算治疗效果。关于合成和现实世界数据集的经验结果表明,所提出的方法可以精确地分解混杂因素并实现比基础线更精确的治疗效果估计。
The fundamental problem in treatment effect estimation from observational data is confounder identification and balancing. Most of the previous methods realized confounder balancing by treating all observed pre-treatment variables as confounders, ignoring further identifying confounders and non-confounders. In general, not all the observed pre-treatment variables are confounders that refer to the common causes of the treatment and the outcome, some variables only contribute to the treatment and some only contribute to the outcome. Balancing those non-confounders, including instrumental variables and adjustment variables, would generate additional bias for treatment effect estimation. By modeling the different causal relations among observed pre-treatment variables, treatment and outcome, we propose a synergistic learning framework to 1) identify confounders by learning decomposed representations of both confounders and non-confounders, 2) balance confounder with sample re-weighting technique, and simultaneously 3) estimate the treatment effect in observational studies via counterfactual inference. Empirical results on synthetic and real-world datasets demonstrate that the proposed method can precisely decompose confounders and achieve a more precise estimation of treatment effect than baselines.