Ensemble Clustering by Noise-Aware Graph Decomposition

Abstract

Ensemble clustering has recently emerged as a powerful tool for aggregating multiple clustering results into a probably better and more robust clustering result. While many ensemble clustering techniques have been developed in recent years, there is still a potential drawback in most of the existing algorithms. They generally neglect the possible noise inside the ensemble of base clusterings, which may exhibit a negative influence on the robustness of the consensus result. To address this, this paper proposes a new ensemble clustering algorithm based on noise-aware graph decomposition. The co-association matrix is first constructed to accumulate information from multiple base clusterings, and then sparsified by means of K-nearest neighbors. By treating the sparsified co-association matrix as the similarity matrix, the corresponding graph is further decomposed into two parts, i.e., the corruption(noise) graph and the good(denoised) graph. In particular, the denoised graph as well as its spectral embedding can be learned simultaneously by solving a trace minimization problem. Finally, upon the learned spectral embedding, the k-means discretization is performed to obtain the final consensus clustering. Experiments on multiple real-world datasets have shown the superiority of the proposed algorithm.