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arXiv · 1104.3083

Narrow scope for resolution-limit-free community detection

V. A. Traag·P. Van Dooren·Y. Nesterov
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Abstract

Detecting communities in large networks has drawn much attention over the years. While modularity remains one of the more popular methods of community detection, the so-called resolution limit remains a significant drawback. To overcome this issue, it was recently suggested that instead of comparing the network to a random null model, as is done in modularity, it should be compared to a constant factor. However, it is unclear what is meant exactly by "resolution-limit-free", that is, not suffering from the resolution limit. Furthermore, the question remains what other methods could be classified as resolution-limit-free. In this paper we suggest a rigorous definition and derive some basic properties of resolution-limit-free methods. More importantly, we are able to prove exactly which class of community detection methods are resolution-limit-free. Furthermore, we analyze which methods are not resolution-limit-free, suggesting there is only a limited scope for resolution-limit-free community detection methods. Finally, we provide such a natural formulation, and show it performs superbly.

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V. A. Traag, P. Van Dooren, Y. Nesterov. 2011-08-01. Narrow scope for resolution-limit-free community detection. https://doi.org/10.1103/physreve.84.016114

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