Title
Computing Top-k Closeness Centrality Faster in Unweighted Graphs.
Abstract
Given a connected graph G = (V,E), the closeness centrality of a vertex v is defined as (n-1 / Sigma_{w V} d(v,w). This measure is widely used in the analysis of real-world complex networks, and the problem of selecting the k most central vertices has been deeply analysed in the last decade. However, this problem is computationally not easy, especially for large networks: in the first part of the paper, we prove that it is not solvable in time O(|E|^{2-epsilonu000f) on directed graphs, for any constant u000fepsilon u003e 0, under reasonable complexity assumptions. Furthermore, we propose a new algorithm for selecting the k most central nodes in a graph: we experimentally show that this algorithm improves significantly both the textbook algorithm, which is based on computing the distance between all pairs of vertices, and the state of the art. For example, we are able to compute the top k nodes in few dozens of seconds in real-world networks with millions of nodes and edges. Finally, as a case study, we compute the 10 most central actors in the IMDB collaboration network, where two actors are linked if they played together in a movie, and in the Wikipedia citation network, which contains a directed edge from a page p to a page q if p contains a link to q.
Year
DOI
Venue
2017
10.1145/3344719
ACM Transactions on Knowledge Discovery from Data (TKDD)
Keywords
DocType
Volume
Centrality, closeness, complex networks
Journal
abs/1704.01077
Issue
ISSN
Citations 
5
1556-4681
8
PageRank 
References 
Authors
0.44
15
5
Name
Order
Citations
PageRank
Elisabetta Bergamini1494.82
Michele Borassi2404.13
Pierluigi Crescenzi3100295.31
Andrea Marino4374.47
Henning Meyerhenke552242.22