Hi Tim, the best software that I know for cluster analysis is NTSYSpc. About how to select variables, I guess it depends on what you want to do. With NTSYSpc you can have an idea of how well relationships in your distance matrix are summarized by the tree topology by computing cophenetic correlations. Also, you can do resampling statistics (jacknife, permutations etc.) and write batch files for running series of analyses. Good luck
Andrea >Hello all, > >I wonder if someone might help with advice on approaches to selecting >variables >when clustering cases (I'm using several methods - Ward, >bagged k-means, etc) - and am working with a large number of apparently >relevant variables. I fear that "noisy" or irrelevant variables may be >weakening my analysis and I would like to refine the input space by >identifying and then eliminating any nuisance variables. > >My concern is to locate procedures (hopefully software) to select a best >sub-set of variables as input; and then refine the input space following >my initial exploratory clustering. I can use discriminant analysis or >simply examine univariate F ratios - but would would seem to simply bias >any subsequent runs towards the classification structure produced by the >first analysis? > >Are there any other procedures for estimating the relative power of the input >variables? and then refining the input space? > > Regards > Tim >Brennan >-- Replies will be sent to the list. >For more information visit http://www.morphometrics.org > > > Dr. Andrea Cardini Hull York Medical School The University of York, Heslington, York YO10 5DD, UK & The University of Hull,Cottingham Road, Hull HU6 7RX, UK tel. 01904 321752 fax 01904 321696 E-mail: [EMAIL PROTECTED] http://www.york.ac.uk/res/fme/people/andrea.htm ------------------------------------------------------------------------- Visita http://domini.interfree.it, il sito di Interfree dove trovare soluzioni semplici e complete che soddisfano le tue esigenze in Internet, ecco due esempi di offerte: - Registrazione Dominio: un dominio con 1 MB di spazio disco + 2 caselle email a soli 18,59 euro - MioDominio: un dominio con 20 MB di spazio disco + 5 caselle email a soli 51,13 euro Vieni a trovarci! Lo Staff di Interfree ------------------------------------------------------------------------- -- Replies will be sent to the list. For more information visit http://www.morphometrics.org
