On bicluster aggregation and its benefits for enumerative solutions

TL;DR

This paper introduces two bicluster aggregation methods to improve the analysis of enumerated biclusters in noisy datasets, reducing redundancy and enhancing solution quality.

Contribution

It proposes novel aggregation techniques based on linkage and overlap rate, addressing fragmentation issues in biclustering results.

Findings

Significantly reduced the number of biclusters

Increased the quality of biclustering solutions

Outperformed state-of-the-art methods in experiments

Abstract

Biclustering involves the simultaneous clustering of objects and their attributes, thus defining local two-way clustering models. Recently, efficient algorithms were conceived to enumerate all biclusters in real-valued datasets. In this case, the solution composes a complete set of maximal and non-redundant biclusters. However, the ability to enumerate biclusters revealed a challenging scenario: in noisy datasets, each true bicluster may become highly fragmented and with a high degree of overlapping. It prevents a direct analysis of the obtained results. To revert the fragmentation, we propose here two approaches for properly aggregating the whole set of enumerated biclusters: one based on single linkage and the other directly exploring the rate of overlapping. Both proposals were compared with each other and with the actual state-of-the-art in several experiments, and they not only significantly reduced the number of biclusters but also consistently increased the quality of the solution.