Cost

The Cost tab of Tune Settings allows you to specify costs for target for scoring purposes. For basic information about costs, see Costs and Benefits.

By default the cost matrix is initially generated based on all the known target values in the build data source. The cost matrix is set to cost values of 1 to start with.

Follow these steps to specify costs:

  1. Before you tune the model, you must select Generate Select Test Results for Model Tuning and run the node, as described in Tuning Classification Models.

  2. Open Properties: for the build node: right-click the node and select Go to Properties from the context menu.

  3. Select the models that you want to tune and click the tune icon tune selected models in the menu bar.

  4. Select Tune from the drop down menu. The Tune Settings dialog opens in a new tab. In Tune Settings, go to the Cost tab.

  5. If you are tuning more than one model, select a model from the Models list in the bottom pane. After you tune the first model, return to this pane and select another model.

  6. Select the target value for which to specify costs.

  7. Decide which is most important:

    • Incorrectly identifying a case as a target class; that is, i a False Positive

    • Incorrectly identifying a case as a non-target class; that is, a False Negative

    False Positive is the default. Click the correct radio button.

  8. Specify a weight for the cost.

  9. Click Apply to add the cost that you just specified to the cost matrix.

  10. Define costs for all target values that you are concerned about.

  11. To apply the matrix, click Tune in the upper right-hand column.

  12. Click Derived Matrix to view the Cost Matrix that you created.

Examine the Derived Cost Matrix. You can continue tuning by changing any selections that you made.

To cancel the tuning, click Reset. Tuning returns to Automatic.

When you done tuning, either click OK to accept the tuning or Cancel to cancel.

To see the impact of the tuning, rerun the model node.