SignedLouvain: Louvain for signed networks
John N. Pougué-Biyong, Renaud Lambiotte
TL;DR
SignedLouvain addresses community detection in signed networks by maximizing a signed modularity $Q$. It introduces a two-layer multiplex framework with hop-bounded moves defined by $d_{+}$ and $d_{-}$ to guide node reassignment. Empirical results on synthetic SBMs and real networks show that SignedLouvain matches or surpasses the accuracy of RelaxedLouvain while remaining substantially faster, with default $d_{+}=1$, $d_{-}=2$ offering a favorable trade-off. The authors provide public data and code to enable reproducibility and further exploration.
Abstract
In this article, we consider the problem of community detection in signed networks. We propose SignedLouvain, an adaptation of the Louvain method to maximise signed modularity, efficiently taking advantage of the structure induced by signed relations. We begin by identifying the inherent limitations of applying the standard Louvain algorithm to signed networks, before introducing a novel variant specifically engineered to overcome these challenges. Through extensive experiments on real-world datasets, we demonstrate that the proposed method not only maintains the speed and scalability of its predecessor but also significantly enhances accuracy in detecting communities within signed networks.
