Comparisons of the reference model with each new model derived from the training dataset under the independent scenario.

The reference model was expanded with six real predictors from the Heart Disease dataset, six non-informative random variables (without stratification by outcome class), and six informative random variables (stratified by outcome class). Shown are the values of the AUC of all new models. ΔAUC shows the difference in AUC relative to the reference model. The AUC of the reference model is 0.758. The DeLong’s test for two correlated ROC curves was used to asses ΔAUC.