How to generate user-friendly summaries of cluster analysis? I used BIRCH and HAC to do clustering on my data.
I want to now what type of information I can include in reports that my users can generate to get more insights on the clusters. I would have to dumb down the statistical terms and represent them as much as possible visually in these reports for my users.
 A: I like a 2D plot that shows the clusters and the actual data points so readers can get an idea of the quality of the clustering. If there are more than two factors, you can put the principle components on the axes, as in my example:

The equivalent 3D plots are only good if the viewer can interact with it get a sense of depth and obscured pieces. Here's a 3D example with the same data.

A: Bubble Charts are a good visual device that you can use to represent your cluster.  Pick your 4 most important variables and plot each cluster using the x and y axis, size and color of bubble to represent the 4 factors.  If you have many variables you can perform a principal components analysis first to reduce them to 4 factors.
http://www.google.com/images?um=1&hl=en&rlz=1I7GGLD_en&tbs=isch:1&aq=f&aqi=g6&oq=&q=bubble%20chart
-Ralph Winters
A: The best method I have found for a non-technical audience is to present a table or plots of the centroids of each cluster along with a description of that cluster. It helps in the business world (not sure your domain) to give a name to each cluster describing it's principle characteristics. Example when clustering customers would be: "Long time loyals" for that cluster that is generally comprised of long tenured customers.
