English

A simple bipartite graph projection model for clustering in networks

Social and Information Networks 2020-07-03 v1 Discrete Mathematics Combinatorics Physics and Society

Abstract

Graph datasets are frequently constructed by a projection of a bipartite graph, where two nodes are connected in the projection if they share a common neighbor in the bipartite graph; for example, a coauthorship graph is a projection of an author-publication bipartite graph. Analyzing the structure of the projected graph is common, but we do not have a good understanding of the consequences of the projection on such analyses. Here, we propose and analyze a random graph model to study what properties we can expect from the projection step. Our model is based on a Chung-Lu random graph for constructing the bipartite representation, which enables us to rigorously analyze the projected graph. We show that common network properties such as sparsity, heavy-tailed degree distributions, local clustering at nodes, the inverse relationship between node degree, and global transitivity can be explained and analyzed through this simple model. We also develop a fast sampling algorithm for our model, which we show is provably optimal for certain input distributions. Numerical simulations where model parameters come from real-world datasets show that much of the clustering behavior in some datasets can just be explained by the projection step.

Keywords

Cite

@article{arxiv.2007.00761,
  title  = {A simple bipartite graph projection model for clustering in networks},
  author = {Austin R. Benson and Paul Liu and Hao Yin},
  journal= {arXiv preprint arXiv:2007.00761},
  year   = {2020}
}
R2 v1 2026-06-23T16:47:01.729Z