VAT: a tool for visual assessment of (cluster) tendency

A method is given for visually assessing the cluster tendency of a set of Objects O = {o/sub 1/, . . . ,o/sub n/} when they are represented either as object vectors or by numerical pairwise dissimilarity values. The objects are reordered and the reordered matrix of pair wise object dissimilarities is displayed as an intensity image. Clusters are indicated by dark blocks of pixels along the diagonal.