Preserving Core Structures of Social Networks via Information Guided Multi-Step Graph Pruning
Yutong Hu, Bingxin Zhou, Jing Wang, Weishu Zhao, Liang Hong
TL;DR
The paper addresses preserving semantic backbone in dense graphs by framing graph semantics with mutual information, specifically tracking $I({\mathcal{G}};{\mathcal{G}}_k)$ and $I({\bm{Y}};{\mathcal{G}}_k)$. It introduces IGPrune, a differentiable, gradient-boosting-inspired multi-step pruning algorithm that progressively removes edges to maximize a lower bound on $I({\mathcal{G}};{\bm{Y}})$ while reducing edges. The framework provides local and global evaluation metrics, including a complexity score, information score, AUC-IC, and IBP, and demonstrates via extensive experiments that IGPrune preserves task-relevant information and reveals interpretable backbones. The empirical results on social and biological networks show improved information–complexity trade-offs and scalable performance relative to baselines, enabling scientific discovery through interpretable backbone extraction.
Abstract
Social networks often contain dense and overlapping connections that obscure their essential interaction patterns, making analysis and interpretation challenging. Identifying the structural backbone of such networks is crucial for understanding community organization, information flow, and functional relationships. This study introduces a multi-step network pruning framework that leverages principles from information theory to balance structural complexity and task-relevant information. The framework iteratively evaluates and removes edges from the graph based on their contribution to task-relevant mutual information, producing a trajectory of network simplification that preserves most of the inherent semantics. Motivated by gradient boosting, we propose IGPrune, which enables efficient, differentiable optimization to progressively uncover semantically meaningful connections. Extensive experiments on social and biological networks show that IGPrune retains critical structural and functional patterns. Beyond quantitative performance, the pruned networks reveal interpretable backbones, highlighting the method's potential to support scientific discovery and actionable insights in real-world networks.
