Top row: slices through the likelihood hypersurface computed for a 2D CR-HR diagram. Scatter is implemented only in the M−T and M−L relations. The likelihood surface is computed by varying only two model parameters at a time: left: Ω_m,σ₈; middle: X_c,w_o; right: σ₈,γ_MT. The central pixel corresponds to the fiducial model and has LH = 0 (white cross). The pixel increment is 1% of the fiducial value for all parameters. The likelihood is computed for an area of 100 deg². Bottom row: same as top but this time for the 3D CR-HR-r_c diagram.