The clustering function hclust has a method = "ward”, and apparently many people use that option. However, the Ward method seems to minimize an increase in the error sums of squares, which are calculated with respect to the cluster mean. However, hclust has only a dissimilarity matrix as an input. With this information, one cannot calculate the cluster means, and consequently cannot use the classic form of the Ward method. My guess is that the function uses a modified version of Ward, but I could not find any information about such a modification. I’m wondering if anybody could explain what is going on here.
Thanks, Peter -- View this message in context: http://r.789695.n4.nabble.com/hclust-with-method-ward-tp2952140p2952140.html Sent from the R help mailing list archive at Nabble.com. ______________________________________________ [email protected] mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
