User guide

Quantity One User Guide
19-16
WPGAMA is a special case of UPGAMA that favors the most recent member
clusters in forming new clusters.
Centroid
Median
Centroid and Median are similar to UPGAMA and WPGAMA, respectively,
but the distance formula contains an additional third term. Centroid and
Median methods are not monatomic hierarchical clustering algorithms. In
other words, the similarity value between cluster k and any other cluster may
be greater than the similarity between cluster p and cluster q. This condition
occurs if the centroids (or medians) of the different clusters have
approximately the same distance as the distances between the samples that
make up the cluster.
Ward's
This method attempts to minimize the information by describing a set of N
samples using a fewer number of clusters.
From our experience, we have found that Ward's method, UPGAMA, and
WPGAMA give the most plausible clusters and are affected the least by
samples that are outliers.
Options
Clicking on the Options button in the Phylogenetic Tree window will open
the Options dialog box.
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