🤖 AI Summary
Existing community detection methods struggle to effectively integrate heterogeneous network structures with node covariates, limiting accurate identification of latent group structures in complex real-world systems such as United Nations General Assembly voting. This work proposes a covariate-augmented spectral clustering framework that extends covariate-assisted spectral clustering to heterogeneous networks for the first time, jointly modeling multi-type connections and node attributes directly on the original heterogeneous network without projection or simplification. The method is theoretically grounded under a heterogeneous node-contextual stochastic block model, providing an upper bound on the misclustering rate. Experiments demonstrate its significant superiority over baseline methods on both synthetic and real UN voting data, successfully uncovering geopolitical alliance structures that jointly reflect voting behavior and node covariates.
📝 Abstract
Community detection is a fundamental problem in network analysis. While many existing methods focus on homogeneous networks, real world networks are often heterogeneous, involving multiple node types and interaction mechanisms. In addition, node specific covariates frequently provide valuable information about the underlying community structure. Existing methodologies typically account for either network heterogeneity or covariate information, but seldom both simultaneously. In this paper, we propose a covariate assisted spectral clustering framework for heterogeneous networks that jointly utilizes network connectivity in a heterogeneous setting and node level covariates. The proposed method extends covariate assisted spectral clustering to heterogeneous settings and operates directly on the heterogeneous network without relying on projection based simplifications. Under a heterogeneous node contextualized stochastic blockmodel, we establish theoretical guarantees for the proposed procedure, including concentration results, eigenspace perturbation bounds, and an explicit upper bound on the misclustering rate. Simulation studies demonstrate that incorporating covariate information substantially improves community recovery and consistently outperforms several benchmark methods. We further apply the proposed framework to United Nations General Assembly voting data, where it reveals meaningful geopolitical structures by combining voting interactions with auxiliary covariate information.