regularization parameter for each outer CV iteration. Theregularization parameter is found by a two-stage approach:a coarse linearly spaced search is followed by a ﬁner lin-early spaced search around the best value found in the coarsesearch. The tuned regularization parameter is then validatedon the test set of the outer CV loop, which remained unseenas the parameter was tuned. All performance metrics are av-eraged over the outer 10 folds and reported in Table 1.