Classification Trees

Select menu: Stats | Multivariate Analysis | Trees | Classification Tree

Use this to form a classification tree.

After you have imported your data, from the menu select
Stats | Multivariate Analysis | Trees | Classification Tree.
Fill in the fields as required then click Run.

You can set additional options before running by clicking Options.

Available data

This lists data structures appropriate to the current input field. The contents will change as you move from one field to the next. Double-click a name to copy it to the current input field or you can type the name.

Groups

Specify a factor for the groupings of the individuals in the tree.

X-variables

Specifies the independent (x) variables available for constructing the tree. You can transfer multiple selections from Available data by holding the Ctrl key on your keyboard while selecting items, then click to move them all across in one action.

Save tree in:

Specifies an identifier name to save the resulting tree in. The tree will be saved within a Genstat Tree data structure.

Prune

The construction of a classification tree generally results in over fitting, that is it continues to extend the branches of the tree beyond the point that can be justified statistically. One solution is to prune the tree to remove the uninformative sub-branches. Clicking this button opens a menu where you can prune the tree.

Action Icons

	Pin	Controls whether to keep the dialog open when you click Run. When the pin is down the dialog will remain open, otherwise when the pin is up the dialog will close.
	Restore	Restore names into edit fields and default settings.
	Clear	Clear all fields and list boxes.
	Help	Open the Help topic for this dialog.