The TREE procedure then generates the tree diagrams. The following data, from Hand, et al. The following statements cluster the variables in the data set Protein . In the first invocation, the tree diagram is presented using the default high resolution graphical output. In both figures, the name of the cluster is displayed on the horizontal axis and the number of clusters is displayed on the vertical or height axis.
Clusters exist at each level of the diagram.
As you proceed up the diagram one level, the number of clusters is two. First, the AXIS1 statement is defined. Next, the TREE procedure is invoked. Clusters exist at each level of the diagram, represented by horizontal line segments. Each vertical line segment represents a point where leaves and branches are connected into progressively larger clusters.