Low-Rank Graphon Learning for Networks

Xinyuan Fan (Tsinghua University) · Feiyan Ma (Tsinghua University) · Chenlei Leng (Hong Kong Polytechnic University) · Weichi Wu (Tsinghua University, Tsinghua University)
computational efficiencyconnection probability matrixconsistencydata analysisempirical performanceestimation accuracyestimation challengesgraphonsidentification issuesinterpolationlarge-scale networkslow-rank representationmodelingsequential algorithmsimulationssubgraph counts

Graphons offer a powerful framework for modeling large-scale networks, yet estimation remains challenging. We propose a novel approach that leverages a low-rank additive representation, yielding both a low-rank connection probability matrix and a low-rank graphon--two goals rarely achieved jointly. Our method resolves identification issues and enables an efficient sequential algorithm based on subgraph counts and interpolation. We establish consistency and demonstrate strong empirical performance in terms of computational efficiency and estimation accuracy through simulations and data analysis.