Title
To cut or not to cut? Assessing the modular structure of brain networks.
Abstract
A wealth of methods has been developed to identify natural divisions of brain networks into groups or modules, with one of the most prominent being modularity. Compared with the popularity of methods to detect community structure, only a few methods exist to statistically control for spurious modules, relying almost exclusively on resampling techniques. It is well known that even random networks can exhibit high modularity because of incidental concentration of edges, even though they have no underlying organizational structure. Consequently, interpretation of community structure is confounded by the lack of principled and computationally tractable approaches to statistically control for spurious modules. In this paper we show that the modularity of random networks follows a transformed version of the Tracy–Widom distribution, providing for the first time a link between module detection and random matrix theory. We compute parametric formulas for the distribution of modularity for random networks as a function of network size and edge variance, and show that we can efficiently control for false positives in brain and other real-world networks.
Year
DOI
Venue
2014
10.1016/j.neuroimage.2014.01.010
NeuroImage
Keywords
Field
DocType
Functional connectivity,Community structure,Graph partitioning methods,Modularity,Random graphs
Normal distribution,Modularity (networks),Random graph,Computer science,Theoretical computer science,Parametric statistics,Spurious relationship,Resampling,Modularity,Random matrix
Journal
Volume
ISSN
Citations 
91
1053-8119
1
PageRank 
References 
Authors
0.36
18
3
Name
Order
Citations
PageRank
Yu-Teng Chang1165.17
Dimitrios Pantazis246438.97
Richard M Leahy31768295.29