Interpreting negative CCC values in a Cluster Analysis

[penguinflies90]

I am doing k-means clustering using fastclus and am getting negative and decreasing CCC values as I increase the number of clusters. The following link says the distribution might be unimodal and long tailed.

http://support.sas.com/kb/22/540.html

What does this mean? Is this talking about the variables I am clustering on or the distribution of the CCC value itself? I am going to try non-parametric clustering to see if that gives me better results. Can anybody suggest anything else apart from that? 

Thanks

[MikeStockstill]

Hello Penguinflies90-

According to the link, "distribution" refers to the CCC.  A number-of-clusters solution is not clearly defined by the CCC in this case.  

Here is a note that provides some analysis strategies to consider.

46314: The Cluster node creates only one big cluster, or does not find clusters in the data

http://support.sas.com/kb/46/314.html

Have a great day.