Estimating the number of clusters via System Evolution

(SE) is developed to estimate the number of clusters (NC) for PAM clustering algorithm. By inspecting whether it is stable that two potential clusters are separated or merged, SE focuses on the separability of two closest clusters among k potential clusters (called twin-clusters) when a data set is divided to k clusters.
SE judges the separability of far clusters, clusters with small clusters near larger clusters or slightly overlapping between clusters.