Drawbacks of ignoring the causal mechanisms when performing imitation learning have recently been acknowledged. Several approaches both to assess the feasibility of imitation and to circumvent causal confounding and causal misspecifications have been proposed in the literature. However, the potential benefits of the incorporation of additional information about the underlying causal structure are left unexplored. An example of such overlooked information is context-specific independence (CSI), i.e., independence that holds only in certain contexts. We consider the problem of causal imitation learning when CSI relations are known. We prove that the decision problem pertaining to the feasibility of imitation in this setting is NP-hard. Further, we provide a necessary graphical criterion for imitation learning under CSI and show that under a structural assumption, this criterion is also sufficient. Finally, we propose a sound algorithmic approach for causal imitation learning which takes both CSI relations and data into account.

翻译：近年来，模仿学习中忽视因果机制的弊端已逐渐被认识。文献中提出了多种评估模仿可行性的方法，以及规避因果混杂和因果规范错误的方法。然而，融入关于底层因果结构的额外信息的潜在益处尚未被探索。此类被忽视的信息中一个例子是上下文特定独立（CSI），即仅在特定上下文中成立的独立关系。我们研究了已知CSI关系时的因果模仿学习问题。我们证明，在此设定下，与模仿可行性相关的决策问题是NP难的。进一步，我们给出了CSI下模仿学习的必要图形化准则，并表明在某种结构假设下该准则也是充分的。最后，我们提出了一种考虑CSI关系与数据的因果模仿学习可靠算法方法。