On Clustering on Graphs with Multiple Edge Types

TL;DR

This paper explores clustering on multi-edge graphs, addressing challenges like metric weight variability, clustering space complexity, and recovering true clusterings, with applications to academic papers and geopolitical data.

Contribution

It generalizes clustering concepts to multi-edge graphs, proposing solutions for weight robustness, clustering space description, and weight recovery, supported by case studies.

Findings

Clustering remains effective despite changes in metric weights.

Efficient description of clustering space is achievable.

Methods can recover ground-truth metric weights.

Abstract

We study clustering on graphs with multiple edge types. Our main motivation is that similarities between objects can be measured in many different metrics. For instance similarity between two papers can be based on common authors, where they are published, keyword similarity, citations, etc. As such, graphs with multiple edges is a more accurate model to describe similarities between objects. Each edge/metric provides only partial information about the data; recovering full information requires aggregation of all the similarity metrics. Clustering becomes much more challenging in this context, since in addition to the difficulties of the traditional clustering problem, we have to deal with a space of clusterings. We generalize the concept of clustering in single-edge graphs to multi-edged graphs and investigate problems such as: Can we find a clustering that remains good, even if we change the relative weights of metrics? How can we describe the space of clusterings efficiently? Can we find unexpected clusterings (a good clustering that is distant from all given clusterings)? If given the ground-truth clustering, can we recover how the weights for edge types were aggregated? %In this paper, we discuss these problems and the underlying algorithmic challenges and propose some solutions. We also present two case studies: one based on papers on Arxiv and one based on CIA World Factbook.