I need help in my research - I have 24 variables and 290 valid cases for cluster analysis. When I perform hierarchical clustering,(Walds method) it gives me almost perfect three clusters (85, 90 and 115 cases in each clusters) the ANOVA is rejected for each of these 24 variables. I have also performed Discriminant analysis which gave me 91.5% accuracy in original grouped cases and 90.5% in cross validated (leave one out ) cases.
My problem is, when I am trying to do a K-means cluster analysis for 3 clusters, Its not giving me proper results, ( 286 in one cluster and 2 each in other) Even a two cluster solution for k-means is not proper (2 in one cluster and others in other) Can anyone tell me what's the problem? I am doing this for my PhD thesis and my guide is insisting on using k-means cluster saying its more robust. Is this true? Is it not possible for me to use hierarchical cluster analysis? Please help me. Thanks in advance Shailaja |
Try using as the k-means starting values
the results from the hierarchical clustering. K-means is sensitive
to starting values. Reordering the data randomly may also help.
Jon Peck (no "h") aka Kim Senior Software Engineer, IBM [hidden email] new phone: 720-342-5621 From: Shailaja Rego <[hidden email]> To: [hidden email] Date: 06/20/2012 07:36 AM Subject: [SPSSX-L] Cluster Analysis - K means or hierarchical? Sent by: "SPSSX(r) Discussion" <[hidden email]> I need help in my research - I have 24 variables and 290 valid cases for cluster analysis. When I perform hierarchical clustering,(Walds method) it gives me almost perfect three clusters (85, 90 and 115 cases in each clusters) the ANOVA is rejected for each of these 24 variables. I have also performed Discriminant analysis which gave me 91.5% accuracy in original grouped cases and 90.5% in cross validated (leave one out ) cases. My problem is, when I am trying to do a K-means cluster analysis for 3 clusters, Its not giving me proper results, ( 286 in one cluster and 2 each in other) Even a two cluster solution for k-means is not proper (2 in one cluster and others in other) Can anyone tell me what's the problem? I am doing this for my PhD thesis and my guide is insisting on using k-means cluster saying its more robust. Is this true? Is it not possible for me to use hierarchical cluster analysis? Please help me. Thanks in advance Shailaja -- View this message in context: http://spssx-discussion.1045642.n5.nabble.com/Cluster-Analysis-K-means-or-hierarchical-tp5713716.html Sent from the SPSSX Discussion mailing list archive at Nabble.com. ===================== To manage your subscription to SPSSX-L, send a message to [hidden email] (not to SPSSX-L), with no body text except the command. To leave the list, send the command SIGNOFF SPSSX-L For a list of commands to manage subscriptions, send the command INFO REFCARD |
Free forum by Nabble | Edit this page |