Cluster Analysis

Command:

Math -> Cluster Analysis...

The command Math/Cluster Analysis provides several methods for constructing dendrograms. The user may select upon five different clustering procedures in combination with four different distance measures. The resulting dendrograms can be used to assign new class numbers to the data objects. When clicking Cluster Analysis the user has first to select the variables to be used for the clustering. Thereafter the dendrogram is calculated and displayed. The dendrogram can be zoomed and panned (use the right mouse button to change the mode of zooming).

Exit	Quit the calculation of dendrograms
Change Variables	Select new variables for calculating the dendrogram. The user may select any combination of variables by means of the variable/object selector which is displayed when the Change Variables button is pressed.
Assign Classes	A dendrogram can be used to assign new class numbers to the objects. The user has to define the distance between the clusters which is used as the criterion for a new class. All clusters which are merged above the specified distance level are assigned new class numbers. The distance level can be set interactively after clicking Assign Classes.
Linkage Type	The dendrogram is recalculated whenever any of the parameters are changed. The user may select one of the following clustering methods: Single Linkage Complete Linkage Average Linkage Ward's Method Flexible Strategy (this method requires an extra parameter alpha, which can be set by using the scrollbar below the Linkage Type box)
Distance Measure	The dendrograms can be calculated using four different distance measures: Euclidian Squared Euclidian Manhattan Jaccard coefficient