Parameters β for the MaNGA and WINGS data and the models of type Mod-B. Left panel: I_e − β plane for the MaNGA data (sky blue crosses) and WINGS (red dots) and for our merger models of type Mod-B (filled squares of different colours according to the age i.e. redshift) at which the seeds are taken: blue (z = 4), green (z = 3), yellow (z = 2), coral (z = 1), and black (z = 0), i.e. the same colour-coding as in Fig. 11. All the models fall along the same straight line, which coincides with low β-limit of data in the positive semi-plane. Right panel: Same plane after perturbing the theoretical data (see text). The meaning of the symbols and colour-coding are the same as in the left panel.