Average-linkage clustering
= Average-linkage clustering
{title2=$d(A,B)=\frac1{|A||B|}\sum_{x\in A,y\in B}d(x,y)$}
Average linkage merges the pair with the smallest mean cross-pair dissimilarity. This differs from the minimum used by <single-linkage clustering> and the maximum used by <complete-linkage clustering>. The convention here weights individual cross-pairs equally; weighting already formed clusters equally is a different algorithm.