Once the clusters are formed, other techniques such as profiling or discriminant analysis can be used to see what internal variables account for the clustering. Some researchers do a preliminary hierarchical clustering to suggest how to start a non-hierarchical procedure. An Illustrative Example See the exercises below for a small example. We'll present examples in class, and maybe post them to the Web later. There are two major ways of clustering, hierarchical and nonhierarchical .
Hierarchical clustering can be agglomerative or divisive .
A dendrogram is a way to represent the results of hierarchical clustering. The mixture model is a conceptual and statistical model for clustering. Consider the following dataset. Compute the matrix of squared Euclidean distances. Do it twice, with different starting points.