Cluster analysis of weighted bipartite networks: a new copula-based approach

PLoS One. 2014 Oct 10;9(10):e109507. doi: 10.1371/journal.pone.0109507. eCollection 2014.

Abstract

In this work we are interested in identifying clusters of "positional equivalent" actors, i.e. actors who play a similar role in a system. In particular, we analyze weighted bipartite networks that describes the relationships between actors on one side and features or traits on the other, together with the intensity level to which actors show their features. We develop a methodological approach that takes into account the underlying multivariate dependence among groups of actors. The idea is that positions in a network could be defined on the basis of the similar intensity levels that the actors exhibit in expressing some features, instead of just considering relationships that actors hold with each others. Moreover, we propose a new clustering procedure that exploits the potentiality of copula functions, a mathematical instrument for the modelization of the stochastic dependence structure. Our clustering algorithm can be applied both to binary and real-valued matrices. We validate it with simulations and applications to real-world data.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Algorithms
  • Cluster Analysis*
  • Computer Simulation*
  • Humans
  • Models, Theoretical*

Grants and funding

The authors acknowledge support from CNR PNR Project “CRISIS Lab” and from the MIUR (FIRB project RBFR12BA3Y). Moreover, Irene Crimaldi is a member of the “Gruppo Nazionale per l'Analisi Matematica, la Probabilità e le loro Applicazioni (GNAMPA)” of the “Istituto Nazionale di Alta Matematica (INdAM)”. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.