Densities in the action space. The grid corresponds to areas in the parameter space delimited in (J_z − J_r) and L_z. From top to bottom: first panel: density of LAMOST contaminants. Second panel: PGS decontaminated pixel-by-pixel, using LAMOST. Third panel: residuals percentages of the pixel-by-pixel PGS decontamination using LAMOST. Fourth panel: PGS decontaminated by the mean of the LAMOST contamination.