Clustering

In broad terms, clustering, or cluster analysis, refers to the process of organizing objects into groups whose members are similar with respect to a similarity or distance criterion. As such, a cluster is a collection of similar objects that are distant from the objects of other clusters. Unlike most classification techniques that aim to assign new observations to one of the many existing groups, clustering is an exploratory procedure that attempts to group objects based on their similarities or distances without relying on any assumptions regarding the number of groups.

Applications of clustering are many; consequently, different techniques have been developed to address the varying analytical objectives. There are applications (such as market research) in which clustering can be used to group objects (customers) based on ...