Comparison between the values of the structural parameters derived from King and f^(ν) best-fit models. The top left panel shows, as crosses, the values of half-mass radii, the top right panel the total masses, the bottom left panel the central mass density and the bottom right panel the mass-to-light ratios. In each panel, the x-axis refers to the values calculated with King models, and the y-axis to those calculated with f^(ν) models; the dotted diagonal line denotes the identity relation. The intrinsic quantity r_M would be best given in parsecs, but it is reported here in arcseconds for easier comparison with the observed profiles and with the projected half-light radius R_e represented in the previous figures.