We propose a new notion of causal contribution which describes the 'intrinsic' part of the contribution of a node on a target node in a DAG. We show that in some scenarios the existing causal quantification methods failed to capture this notion exactly. By recursively writing each node as a function of the upstream noise terms, we separate the intrinsic information added by each node from the one obtained from its ancestors. To interpret the intrinsic information as a causal contribution, we consider 'structure-preserving interventions' that randomize each node in a way that mimics the usual dependence on the parents and do not perturb the observed joint distribution. To get a measure that is invariant across arbitrary orderings of nodes we propose Shapley based symmetrization. We describe our contribution analysis for variance and entropy, but contributions for other target metrics can be defined analogously.
翻译:我们提出了一个因果贡献的新概念, 描述 DAG 目标节点上的节点贡献的“ 内在” 部分。 我们显示, 在某些情况下, 现有的因果量化方法未能准确地捕捉到这个概念 。 通过反复撰写每个节点作为上游噪音术语的函数, 我们将每个节点所增加的内在信息与其祖先从它祖先那里获得的信息区分开来 。 为了将内在信息解释为因果贡献, 我们考虑“ 结构保护干预”, 随机将每个节点排列成随机模式, 从而模仿对父母的通常依赖, 而不是破坏所观察到的联合分布 。 要获得一个在任意的节点顺序上变化不定的尺度, 我们建议基于“ 虚度” 的对齐称。 我们描述我们对差异和 共性的贡献分析, 但是对其它目标指标的贡献可以作类似的定义 。