# Statistics

Available statistics tables depend on the measurement level of the dependent variable, the growing method, and other settings.

Model

**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.

Independent 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.

Node Performance

**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.