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arXiv · 1907.08048

Total variation based community detection using a nonlinear optimization approach

Andrea Cristofari·Francesco Rinaldi·Francesco Tudisco
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Abstract

Maximizing the modularity of a network is a successful tool to identify an important community of nodes. However, this combinatorial optimization problem is known to be NP-complete. Inspired by recent nonlinear modularity eigenvector approaches, we introduce the modularity total variation $TV_Q$ and show that its box-constrained global maximum coincides with the maximum of the original discrete modularity function. Thus we describe a new nonlinear optimization approach to solve the equivalent problem leading to a community detection strategy based on $TV_Q$. The proposed approach relies on the use of a fast first-order method that embeds a tailored active-set strategy. We report extensive numerical comparisons with standard matrix-based approaches and the Generalized RatioDCA approach for nonlinear modularity eigenvectors, showing that our new method compares favourably with state-of-the-art alternatives.

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Andrea Cristofari, Francesco Rinaldi, Francesco Tudisco. 2019-07-18. Total variation based community detection using a nonlinear optimization approach. https://doi.org/10.1137/19m1270446

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