Title
Exact maximum-likelihood method to detect patterns in real networks
Abstract
In order to detect patterns in real networks, randomized graph ensembles that preserve only part of the topology of an observed network are systematically used as fundamental null models. However, their generation is still problematic. The existing approaches are either computationally demanding and beyond analytic control, or analytically accessible but highly approximate. Here we propose a solution to this long-standing problem by introducing an exact and fast method that allows to obtain expectation values and standard deviations of any topological property analytically, for any binary, weighted, directed or undirected network. Remarkably, the time required to obtain the expectation value of any property is as short as that required to compute the same property on the single original network. Our method reveals that the null behavior of various correlation properties is different from what previously believed, and highly sensitive to the particular network considered. Moreover, our approach shows that important structural properties (such as the modularity used in community detection problems) are currently based on incorrect expressions, and provides the exact quantities that should replace them.
Year
Venue
Keywords
2011
Computing Research Repository
null model,expected value,standard deviation,maximum likelihood method,random graph
Field
DocType
Volume
Mathematical optimization,Expression (mathematics),Maximum likelihood,Expectation value,Algorithm,Null model,Standard deviation,Modularity,Mathematics,Binary number,Topological property
Journal
abs/1103.0
Citations 
PageRank 
References 
0
0.34
0
Authors
2
Name
Order
Citations
PageRank
Tiziano Squartini16711.86
Diego Garlaschelli29018.49