Estimating the number of communities in a network

M. E. J. Newman; Gesine Reinert

doi:10.1103/physrevlett.117.078301

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arXiv · 1605.02753

Estimating the number of communities in a network

M. E. J. Newman·Gesine Reinert

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Abstract

Community detection, the division of a network into dense subnetworks with only sparse connections between them, has been a topic of vigorous study in recent years. However, while there exist a range of powerful and flexible methods for dividing a network into a specified number of communities, it is an open question how to determine exactly how many communities one should use. Here we describe a mathematically principled approach for finding the number of communities in a network using a maximum-likelihood method. We demonstrate the approach on a range of real-world examples with known community structure, finding that it is able to determine the number of communities correctly in every case.

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M. E. J. Newman, Gesine Reinert. 2016-08-23. Estimating the number of communities in a network. https://doi.org/10.1103/physrevlett.117.078301

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