Probability of rejection of the abundance profiles with and without the iron plateau. The dashed lines mark (1 − P) = 0.90, hence the yellow points shows clusters for which both the single- and double-component models are rejected at >90% c.l. Clusters colored in red favor the double-component model, while both models provide similar quality fits to the clusters colored in blue. In these cases, the double-component model returns a slightly lower goodness because of the inclusion of an additional parameter in the fit.