Projected number density profiles of faint galaxies around the 1st ranked (black) and 2nd ranked galaxy of the groups (grey). Upper panel: profiles for the mock CG (CGs2) sample when incompleteness by fibre collision and low surface brightness are included; second panel: profiles for the CGs in the 2MASS (2MCGs) shown in Fig. 7. Faint galaxies in the 2MCGs are extracted from the SDSS. Error bars are the standard deviations computed with 100 bootstraps. Bottom panels: ratios between the profiles around CGs2 and the profiles around the 2MCGs. Dotted lines shows the corresponding ratios when no incompleteness is included in the mock sample. Errors are computed by error propagation.