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Re: clustering [message #54962 is a reply to message #54850]

Mon, 23 July 2007 10:14

little davey
Messages: 5
Registered: June 2007

Junior Member

Is it the case that you MUST use standardize() before you call
CLUST_WTS()? The documentation does not say so, but I suspect from
the code, and, I actually tried it with the initial poster's data, and
got 4 clusters (he wanted 5, but this would appear to be a tough data
set to cluster, as variables "2" and "3" are close to each other).

As I posted an hour ago, part of the source code for CLUST_WTS() is:

;Normalized uniformly random cluster weights.
;;Weights = RANDOMU(SEED, N_Variables, N_Clusters) + Zero
av1 = average(array[0,*])
av2 = average(array[1,*])
Weights = RANDOMU(SEED, N_Variables, N_Clusters) + Zero
for k = 0L, N_Clusters-1 do Weights[*,k] = $
(Weights[*,k] / TOTAL(Weights[*,k])) * Variable_Wts

However, the variables AV1 and AV2 are NOT USED ANYWHERE IN THE CODE,
so I suspect that the data is not "normalized" correctly in
CLUST_WTS. The use of STANDARDIZE() may be necessary for CLUST_WTS to
work.

-- Dave K --

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[Message index]

		clustering By: nivedita.raghunath on Tue, 17 July 2007 08:36
		Re: clustering By: Vince Hradil on Thu, 19 July 2007 10:30
		Re: clustering By: nivedita.raghunath on Thu, 19 July 2007 09:12
		Re: clustering By: Vince Hradil on Thu, 19 July 2007 13:46
		Re: clustering By: Conor on Wed, 18 July 2007 12:07
		Re: clustering By: Vince Hradil on Mon, 23 July 2007 11:22
		Re: clustering By: James Kuyper on Mon, 23 July 2007 11:16
		Re: clustering By: little davey on Mon, 23 July 2007 10:14
		Re: clustering By: little davey on Mon, 23 July 2007 09:08
		Re: clustering By: Conor on Mon, 23 July 2007 06:49
		Re: clustering By: nivedita.raghunath on Mon, 23 July 2007 06:45
		Re: Clustering By: Kai Mühlbauer on Tue, 01 November 2011 03:01
		Re: Clustering By: Kai Muehlbauer on Mon, 31 October 2011 08:40
		Re: Clustering By: Jeremy Bailin on Tue, 01 November 2011 12:16
		Re: Clustering By: kidpix on Mon, 31 October 2011 04:56
		Re: Clustering By: Kai Mühlbauer on Fri, 28 October 2011 10:07
		Re: clustering By: kisCA on Wed, 07 March 2012 13:37
		Re: clustering By: Russell[1] on Wed, 07 March 2012 09:32

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