Representation of the absolute relative difference between the numerical and analytical estimates of the sample mean of the structure function, ⟨SF⟩, at three distinct separations s. Each coloured square corresponds to one experiment based on the same 100 realisations of the velocity field with L_inj = 100 kpc and various binning sizes (y-axis) and β-models core radii (x-axis). Small red crosses indicate locations where the binning size is larger than s.