Example of average SEDs produced employing the uncorrected (left) and corrected (right) photometry (blue). The effect of the corrections applied is to increase the flux bluewards of the Lyα and reduce the optical and UV Fe II bumps. In addition, the strong Hα emission in the observed-frame H band (pink) is reduced in the corrected data-set. The grey clouds of points are the photometric data used to produce the SED; the coloured diamonds (same colour-code as in left panel of Fig. 3) are the median luminosities. The solid grey line represents the number of objects contributing to each spectral channel. The average quasar SED from Krawczyk et al. (2013), scaled to the 3000 Å total luminosity, is shown in green as a comparison. The light blue and orange shaded areas represent the regions where the L_opt and the L_NIR terms in the covering factor proxy R are respectively evaluated (see Sect. 3.5). The average z and log(L_bol) of the parameter space represented by these SEDs are denoted in the top string.