Supervised feature group selection
Echoing the hierarchical CFR concept, an additional feature selection step is proposed that restricts the features used for model building to a set of pre-defined feature groups:MeshVolumeshape features (including MeshVolume)first-order featurestexture featuresand﻿ this set is augmented with all pair-wise combinations of groups 2–4 plus a final group that includes all features, giving eight feature groups in total. The CFR and feature group selection steps are applied prior, and in addition to any other feature selection steps that may be part of the classification model fitting, e.g., the classifier used in this work includes LASSO regularization that employs embedded feature selection [Flow diagram showing the model discovery pipeline within nested cross-validation loops (CV) to perform parameter tuning and performance evaluation