Different attribution scores have been proposed to quantify the relevance of database tuples for query answering in databases; e.g. Causal Responsibility, the Shapley Value, the Banzhaf Power-Index, and the Causal Effect. They have been analyzed in isolation. This work is a first investigation of score alignment depending on the query and the database; i.e. on whether they induce compatible rankings of tuples. We concentrate mostly on causality-based scores; and provide a syntactic dichotomy result for queries: on one side, pairs of scores are always aligned, on the other, they are not always aligned. It turns out that the presence of exogenous tuples makes a crucial difference in this regard.
翻译:为量化数据库元组对查询应答的相关性,已有多种归因评分方法被提出,例如因果责任、Shapley值、Banzhaf权力指数和因果效应。这些方法以往均被独立分析。本研究首次探讨评分对齐与查询及数据库的依赖关系,即它们是否诱导出兼容的元组排序。我们主要聚焦于基于因果关系的评分方法,并针对查询提出语法二分定理:一方面,部分评分对始终保持对齐;另一方面,部分评分对并非始终对齐。研究结果表明,外生元组的存在对此具有关键性影响。