From Chain to Tree: Refining Chain-like Rules into Tree-like Rules on Knowledge Graphs
Wangtao Sun, Shizhu He, Jun Zhao, Kang Liu
TL;DR
This work addresses the limited expressive power of chain-like rules in knowledge graph reasoning by introducing tree-like rules, which incorporate branch atoms to constrain grounding values. It presents a three-stage framework—Forward Reasoning, Backward Reasoning, and Candidate Atoms Selection—to refine chain-like rules into tree-like forms, leveraging a matrix-based KG representation for efficient reasoning. Across four public KGs and multiple chain-rule sources, the refined tree-like rules consistently achieve higher $sc$ and lead to improved link prediction performance, with gains correlating to graph density. The approach thus enhances interpretability and predictive accuracy in KG reasoning, providing a versatile method to upgrade existing rule-induction methods.
Abstract
With good explanatory power and controllability, rule-based methods play an important role in many tasks such as knowledge reasoning and decision support. However, existing studies primarily focused on learning chain-like rules, which limit their semantic expressions and accurate prediction abilities. As a result, chain-like rules usually fire on the incorrect grounding values, producing inaccurate or even erroneous reasoning results. In this paper, we propose the concept of tree-like rules on knowledge graphs to expand the application scope and improve the reasoning ability of rule-based methods. Meanwhile, we propose an effective framework for refining chain-like rules into tree-like rules. Experimental comparisons on four public datasets show that the proposed framework can easily adapt to other chain-like rule induction methods and the refined tree-like rules consistently achieve better performances than chain-like rules on link prediction. The data and code of this paper can be available at https://anonymous.4open.science/r/tree-rule-E3CD/.
