Linkage centroid

There exist several methods of hierarchical clustering which use diverse measures of distance or similarity, respectively, e.g., single linkage, complete linkage, average linkage, centroid linkage, and Ward s method (Sharaf et al. [1986], Massart et al. [1988], Otto [1998] Danzer et al. [2001]). 

Centroid Linkage Here, the centroid calculated by the average of a cluster is applied as the basis for aggregation without distorting the cluster space ... 

Median Linkage For determination of the centroid, the median can also be used ... 

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