Subject: CCL:Cluster analysis (fwd)

From: James Smith <[email-masked]>
Date: Mon, 10 Apr 2000 10:52:51 +0100 (BST)

Make sure that your chosen method doesn't violate the ultrametric 
inequality rule. I use Geometric (cluster centred), minimal variance,
agglomerative clustering [1] can be applied to an rms difference-distance
matrix and the number of significant clusters identified by Mojena's
Stopping Rule No.1 (p < 0.05) [2]. 

1 - Ward, J. H. (1963). Hierarchical Grouping for Evaluating Clustering
Methods, Journal of the American Statistics Association, 58, 236-244.

2 -  Mojena, R. (1977). Hierarchical grouping methods and stopping rules:
An evaluation, Computer Journal, 20 (4), 359-363.

I hope this helps

James

_________________________________________________________________________

 James Smith       Drug Design Group           +44 1223 338600 (College)
 St John's College Department of Pharmacology  +44 1223 331985 (Office)
 Cambridge         University of Cambridge     +44 1223 331740 (Fax)
 CB2 1TP           CB2 1QJ                     [email-masked]   
 United Kingdom    United Kingdom       http://www.cus.cam.ac.uk/~js252
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