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arXiv · 2012.02676

Community detection using fast low-cardinality semidefinite programming

Po-Wei Wang·J. Zico Kolter
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Abstract

Modularity maximization has been a fundamental tool for understanding the community structure of a network, but the underlying optimization problem is nonconvex and NP-hard to solve. State-of-the-art algorithms like the Louvain or Leiden methods focus on different heuristics to help escape local optima, but they still depend on a greedy step that moves node assignment locally and is prone to getting trapped. In this paper, we propose a new class of low-cardinality algorithm that generalizes the local update to maximize a semidefinite relaxation derived from max-k-cut. This proposed algorithm is scalable, empirically achieves the global semidefinite optimality for small cases, and outperforms the state-of-the-art algorithms in real-world datasets with little additional time cost. From the algorithmic perspective, it also opens a new avenue for scaling-up semidefinite programming when the solutions are sparse instead of low-rank.

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Po-Wei Wang, J. Zico Kolter. 2020-12-04. Community detection using fast low-cardinality semidefinite programming. https://arxiv.org/abs/2012.02676

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