Probability distribution function for the M_∗ determination of a particular galform SFH. The vertical axis in all panels corresponds to different input frac_AGN. Each panel corresponds to a different AGN SED added to the stellar light: left is for the Type-1 AGN, the middle panel corresponds to the intermediate AGN type, and right panel plots the results for the Type-2 AGN. The colour indicates the level of probability, blue being the lowest probability, and red the highest. The true log M_∗ for the particular simulated galaxy is 10.39 in solar units.