Fig. 2

Illustration of removing weak (a) features and (b) feature pairs. a Features for which |r^f|<T₁ are removed. Features for which r^f>T₁ are risk increasing features, and features for which r^f<−T₁ are the risk decreasing features. b Similarly, features pairs for which \(\left |r^{f_{i}f_{j}}_{c_{i}c_{j}}\right |<T_{2}\) are removed. Feature pairs for which \(r^{f_{i}f_{j}}_{c_{i}c_{j}}>T_{2}\) are risk increasing feature pairs, and feature pairs for which \(r^{f_{i}f_{j}}_{c_{i}c_{j}}<-T_{2}\) are risk decreasing. Red and green, respectively, denote risk increasing and risk decreasing features and feature pairs