Redshift distributions of random clones z_rand, whose parent galaxies are situated at photometric redshifts z_gal. Top: unwindowed clones are scattered over the entire redshift range, depending on the brightness, and hence z_max, of parent galaxies. Bottom: for the windowed randoms, 71.5% of a galaxy’s random clones are scattered within a ±1σ symmetric volume, centred on the location of the parent galaxy [we display σ = 3 × 10⁶ (h⁻¹ Mpc)³ randoms here, for a clearer illustration]. We note that the symmetry is in volume coordinates, hence in redshift/comoving coordinates the windows are extended in the direction of the observer, and slightly squashed in the outward direction. This figure is closely based on a similar plot presented by Farrow et al. (2015) for GAMA galaxies and randoms (their Fig. 3). Plateaus in the red curves, on approach to redshift zero, correspond to faint, very low-redshift galaxies which are excluded from our analysis.