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From: markh@csd4.csd.uwm.edu (Mark William Hopkins)
Newsgroups: comp.theory
Subject: Least-squares clustering.
Message-ID: <11014@uwm.edu>
Date: 13 Apr 91 17:47:54 GMT
Article-I.D.: uwm.11014
Sender: news@uwm.edu
Organization: University of Wisconsin - Milwaukee
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   I have a particular algorithm in mind.  It takes a set, S, of N-vectors
and partitions it into sets S1, S2 such that

		    sigma(S1) + sigma(S2) is minimized
                    where
                       sigma(S) = total square deviation of S
			  (that is, sum x in S: |x - average(S)|^2)

It runs sequentually through S and calculates S1 and S2 in one pass.