Figure 2

Overview of selected features. Feature selection with L1 regularization with increasing λ₁ values (from top to bottom) for CoEPrA regression task I. Left vertical axis: λ₁ Right vertical axis: number of remaining features after a cycle of L1 regularization with the corresponding λ₁ value. Horizontal axis displays the feature index. The initial number of features is 6219. The colors, varying from black to yellow, exhibit how often specific features reappear in the selection procedure after they disappeared in the selection round before. For instance yellow marks features that reappeared seven times for the eight different λ₁ values considered.