Adaptive Noise Immune Cluster Ensemble Using Affinity Propagation

Cluster ensemble is one of the main branches in the ensemble learning area which is an important research focus in recent years. The objective of cluster ensemble is to combine multiple clustering solutions in a suitable way to improve the quality of the clustering result. In this paper, we design a new noise immune cluster ensemble framework named as AP²CE to tackle the challenges raised by noisy datasets. AP²CE not only takes advantage of the affinity propagation algorithm (AP) and the normalized cut algorithm (Ncut), but also possesses the characteristics of cluster ensemble. Compared with traditional cluster ensemble approaches, AP²CE is characterized by several properties. (1) It adopts multiple distance functions instead of a single Euclidean distance function to avoid the noise related to the distance function. (2) AP²CE applies AP to prune noisy attributes and generate a set of new datasets in the subspaces consists of representative attributes obtained by AP. (3) It avoids the explicit specification of the number of clusters. (4) AP²CE adopts the normalized cut algorithm as the consensus function to partition the consensus matrix and obtain the final result. In order to improve the performance of AP²CE, the adaptive AP²CE is designed, which makes use of an adaptive process to optimize a newly designed objective function. The experiments on both synthetic and real datasets show that (1) AP²CE works well on most of the datasets, in particular the noisy datasets; (2) AP²CE is a better choice for most of the datasets when compared with other cluster ensemble approaches; (3) AP²CE has the capability to provide more accurate, stable and robust results.