🤖 AI Summary
This work addresses the challenges of multi-label node classification on heterogeneous graphs, where structural heterogeneity and shared label semantics often lead to semantic dilution or insufficient coverage in existing methods. The authors propose FOCAL, a novel framework that theoretically reveals, for the first time, how neighbor expansion degrades attention quality. To mitigate the inherent tension between coverage and semantic focus, FOCAL introduces a dual-path attention architecture: Coverage-Oriented Attention (COA) enables unconstrained aggregation of heterogeneous contextual information, while Anchor-Oriented Attention (AOA) leverages metapaths to concentrate on dominant semantics. Experimental results demonstrate that FOCAL significantly outperforms state-of-the-art approaches across multiple benchmark datasets, achieving superior prediction performance and effectively alleviating semantic dilution.
📝 Abstract
Heterogeneous graphs have attracted increasing attention for modeling multi-typed entities and relations in complex real-world systems. Multi-label node classification on heterogeneous graphs is challenging due to structural heterogeneity and the need to learn shared representations across multiple labels. Existing methods typically adopt either flexible attention mechanisms or meta-path constrained anchoring, but in heterogeneous multi-label prediction they often suffer from semantic dilution or coverage constraint. Both issues are further amplified under multi-label supervision. We present a theoretical analysis showing that as heterogeneous neighborhoods expand, the attention mass allocated to task-critical (primary) neighborhoods diminishes, and that meta-path constrained aggregation exhibits a dilemma: too few meta-paths intensify coverage constraint, while too many re-introduce dilution. To resolve this coverage-anchoring conflict, we propose FOCAL: Fusion Of Coverage and Anchoring Learning, with two components: coverage-oriented attention (COA) for flexible, unconstrained heterogeneous context aggregation, and anchoring-oriented attention (AOA) that restricts aggregation to meta-path-induced primary semantics. Our theoretical analysis and experimental results further indicates that FOCAL has a better performance than other state-of-the-art methods.