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Title: Multiway Spherical Clustering via Degree-Corrected Tensor Block Models
We consider the problem of multiway clustering in the presence of unknown degree​ ​heterogeneity. Such data problems arise commonly in applications such as recommendation systems, neuroimaging, community detection, and hypergraph partitions​ ​in social networks. The allowance of degree heterogeneity provides great flexibility​ ​in clustering models, but the extra complexity poses significant challenges in both​ ​statistics and computation. Here, we develop a degree-corrected tensor block model​ ​with estimation accuracy guarantees. We present the phase transition of clustering​ ​performance based on the notion of angle separability, and we characterize three​ ​signal-to-noise regimes corresponding to different statistical-computational behaviors.​ ​In particular, we demonstrate that an intrinsic statistical-to-computational gap emerges​ ​only for tensors of order three or greater.​ ​Further, we develop an efficient polynomial time algorithm that provably achieves exact​ ​clustering under mild signal conditions. The​ ​efficacy of our procedure is demonstrated​ ​through both simulations and analyses of​ ​Peru Legislation dataset.  more » « less
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Proceedings of the 25th International Conference on Artificial Intelligence and Statistics (AISTATS) 2022, Valencia, Spain.
Medium: X
Sponsoring Org:
National Science Foundation
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