To use
the Decision Tree node to interactively train
and prune a decision tree, complete the following steps:
-
From the
Model tab on the Toolbar, select the Decision Tree node
icon. Drag the node into the Diagram Workspace.
-
In the
Diagram Workspace, right-click the Decision Tree node, and select
Rename from the resulting menu. Enter
Interactive Decision Tree
and then click
OK in the window that opens.
-
Connect
the Replacement node to the Interactive Decision Tree node.
-
Select
the Interactive Decision Tree node. In the Properties Panel, scroll
down to view the Train properties, and click on the ellipses that
represent the value of
Interactive. The
Interactive Decision Tree window opens.
-
Select
the root node (at this point, the only node in the tree), and then
from the
Train menu, select
Split
Node. The
Split Node window opens
that lists the candidate splitting rules ranked by logworth (-Log(p)).
The FREQUENCY_STATUS_97NK rule has the highest logworth. Ensure that
this row is selected, and click
OK.
-
The tree
now has two additional nodes. Select the lower-left node (where FREQUENCY_STATUS_97NK
is 3 or 4), and then from the
Train menu,
select
Split Node. In the Split Node window
that opens, select MONTHS_SINCE_LAST_GIFT, which ranks second in logworth,
and click
Edit Rule to manually specify the
split point for this rule. The
Interval Splitting Rule window opens.
Enter
8
as the
New split point, and click
Add Branch. Then, select Branch
2 (>= 8.5) and click
Remove Branch. Click
OK.
Ensure
that MONTHS_SINCE_LAST_GIFT is selected in the
Split Node window, and click
OK.
-
Select
the first generation node that you have not yet split (where FREQUENCY_STATUS_97NK
is 1, 2, or Missing). From the
Train menu,
select
Split Node. In the
Split
Node window that opens, ensure that PEP_STAR is selected,
and click
OK.
The tree
now has seven (four of them, leaf) nodes. The nodes are colored from
dark to light, corresponding to low to high percentages of correctly
classified observations.
-
Select
the lower-right node (where FREQUENCY_STATUS_97NK is 1, 2, or Missing
and PEP_STAR is 0 or Missing). From the
Train menu, select
Train Node. This selection causes
SAS Enterprise Miner to continue adding generations of this node until
a stopping criterion is met. For more information about stopping criteria
for decision trees, see the SAS Enterprise Miner Help.
Note: In the
Interactive Decision Tree window, you can prune decision
trees. However, in this example, you will leave the tree in its current
state.
-
Close
the
Interactive Decision Tree window, and
click
Yes in the confirmation window that opens.