WPGMA

WPGMA stands for Weighted Pair-Group Method with Arithmetic mean.

Assume that there are three clusters called C1, C2 and C3 including n1, n2 and n3 number of rows. Clusters C2 and C3 are aggregated to form a new single cluster called C4.

The distance between cluster C1 and the new cluster C4 is calculated as:

See also:

Clustering Methods Overview