One-dimensional marginal posteriors on the parameters of the richness–mass relation (amplitude lnA_λ, mass slope B_λ and redshift evolution C_λ), as well as the intrinsic scatter in richness σ_λ and the correlation between the intrinsic SZe and richness scatter ρ in the different models considered (prj: projection effects; cont: contamination; mass dep: mass-dependent scatter; prj+: projection effect with free amplitude; prj++: projection effects with free amplitude, richness and redshift trends; prj+cont: projection effects with contamination). The stars denote the median. The darker (faded) line extends from the 16th (2.5th) to the 84th (97.5th) percentile.