Chapter 10. reports – Bio-Rad Quantity One 1-D Analysis Software User Manual
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Chapter 10. Reports
10-17
WPGAMA
Weighted pair group method using arithmetic averages. This is also called Average
Linkage.
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.
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