Mean infall velocity as a function of distance to the group center for biased samples. Dashed line indicates the mean velocity obtained from the mock with errors included (biased mock), and the dot-dashed line corresponds to the Cosmicflows-3 sample (CF3S). For comparison, we include the mean infall velocity for the unbiased mock(solid line). Error bars correspond to the uncertainty in the mean infall velocities from CF3S. The shaded region indicates the variance obtained from 25 mocks without (with) errors included in the catalog realizations.