Pearl and Verma developed d-separation as a widely used graphical criterion to reason about the conditional independencies that are implied by the causal structure of a Bayesian network. As acyclic ground probabilistic logic programs correspond to Bayesian networks on their dependency graph, we can compute conditional independencies from d-separation in the latter. In the present paper, we generalize the reasoning above to the non-ground case. First, we abstract the notion of a probabilistic logic program away from external databases and probabilities to obtain so-called program structures. We then present a correct meta-interpreter that decides whether a certain conditional independence statement is implied by a program structure on a given external database. Finally, we give a fragment of program structures for which we obtain a completeness statement of our conditional independence oracle. We close with an experimental evaluation of our approach revealing that our meta-interpreter performs significantly faster than checking the definition of independence using exact inference in ProbLog 2.

通过将概率逻辑程序结构抽象化为程序结构，并给出一个正确的元解释器来决定给定外部数据库的程序结构是否意味着某个特定的条件独立性陈述，本研究将Pearl和Verma的有向分离理论推广到非ground情况，进而从d-separation中计算条件独立性，实验评估结果显示，比起在ProbLog 2中使用精确推理来检查独立性定义，我们的元解释器的性能明显更快。

关于概率逻辑程序结构中隐藏的独立性