Available statistics tables depend on the measurement level of the dependent variable, the growing method, and other settings.
Summary. The summary includes the method used, the variables included in the model, and the variables specified but not included in the model.
Risk. Risk estimate and its standard error. A measure of the tree's predictive accuracy.
- For categorical dependent variables, the risk estimate is the proportion of cases incorrectly classified after adjustment for prior probabilities and misclassification costs.
- For scale dependent variables, the risk estimate is within-node variance.
Classification table. For categorical (nominal, ordinal) dependent variables, this table shows the number of cases classified correctly and incorrectly for each category of the dependent variable. Not available for scale dependent variables.
Cost, prior probability, score, and profit values. For categorical dependent variables, this table shows the cost, prior probability, score, and profit values used in the analysis. Not available for scale dependent variables.
Importance to model. For the CRT growing method, ranks each independent (predictor) variable according to its importance to the model. Not available for QUEST or CHAID methods.
Surrogates by split. For the CRT and QUEST growing methods, if the model includes surrogates, lists surrogates for each split in the tree. Not available for CHAID methods. See the topic Surrogates for more information.
Summary. For scale dependent variables, the table includes the node number, the number of cases, and the mean value of the dependent variable. For categorical dependent variables with defined profits, the table includes the node number, the number of cases, the average profit, and the ROI (return on investment) values. Not available for categorical dependent variables without defined profits. See the topic Profits for more information.
By target category. For categorical dependent variables with defined target categories, the table includes the percentage gain, the response percentage, and the index percentage (lift) by node or percentile group. A separate table is produced for each target category. Not available for scale dependent variables or categorical dependent variables without defined target categories. See the topic Selecting Categories for more information.
Rows. The node performance tables can display results by terminal nodes, percentiles, or both. If you select both, two tables are produced for each target category. Percentile tables display cumulative values for each percentile, based on sort order.
Percentile increment. For percentile tables, you can select the percentile increment: 1, 2, 5, 10, 20, or 25.
Display cumulative statistics. For terminal node tables, displays additional columns in each table with cumulative results.
To Select Statistics Output
This feature requires the Decision Trees option.
- From the menus choose:
- In the main Decision Tree dialog, click Output.
- Click the Statistics tab.