Density plot of correctly predicted coronal holes (TPR) versus erroneously predicted coronal holes (FPR) obtained from intensity-based coronal hole region segmentation using all attributes. The red crosses denote the individual results for the TPR and FPR for each of the 100 iterations, according to the training and evaluation protocol described in Section 4.2. (a) Decision Tree, (b) linear SVM, (c) random forest, (d) SVM.