Representation of the 35 coefficients w_j of a logistic regression model p(I_main|counts), trained to predict whether a cluster was selected in the primary cluster sample. The 35 features are surface brightness in 7 radial annuli, associated to the 5 components indicated in legend (counts from the galaxy cluster of interest, from neighbouring AGN, fore- and background counts, counts from foreground stars, counts from other neighbouring galaxy clusters). High absolute value of a coefficient indicates high importance of the associated feature (Eq. (6)).