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tokens: properties across luminosity and redshift indicates very similar underlying physical mechanisms that can be understood in terms of Eigenvector 1 ( Boroson Green 1992 ; Francis et al. 1992 ) where the Eddington ratio drives the relative strength of the lines, and orientation effects influences the observed kinematics of the lines ( Shen Ho 2014 ). The specific local physical conditions that regulate the accretion rate then account for the majority of the inter-quasar variation. In this section, we will investigate whether the targets selected are simply scaled-up version of average quasars, or remarkable in some sense. 6.1. Comparison to global population The QSOs selected for this study lie amongst the brightest values of compared to the spectroscopically confirmed SDSS QSOs ( Shen et al. 2011 ), which are uniformly selected to 90 percent completeness ( Richards et al. 2002a ; Vanden Berk et al. 2005 ). It is clear that the sample presented here represents some of the brightest quasars existing between redshift 1 and 2. It is therefore potentially a biased subset of the global quasar population. Quasars have previously been shown to exhibit a high degree of homogeneity over many orders of magnitude ( Dietrich et al. 2002 ), but this is only true for quasars resembling average quasars and not exotic sub-types. To ensure that the targets selected for this sample are not outliers in color, the spectrophotometric colors are compared to those of the quasar population presented in Pâris et al. (2014) 3 . We show the comparison in Fig. . From the magnitudes, we first confirm that the quasars selected here are among the intrinsically brightest visible in -band with a 2.7 sigma magnitude distance from the mean absolute -band magnitude, normalized at redshift 2, of the full SDSS quasar catalog for DR10. Despite their luminosities the colors are representative of the subset fulfilling the selection criteria. As a consistency check, the composite generated in this work is used to fit for the dust content of quasars with varying degree of extinction and consistent results were obtained as compared with composites generated from other subsamples of the parent population. For a comparison between SDSS and quasars detected in GALEX, UKIDSS, WISE, 2MASS and Spitzer , see Krawczyk et al. (2013) . Fig. 6 Quasar color, , as a function of redshift, . The full quasar sample from SDSS DR10 ( Pâris et al. 2014 ) is shown in gray color. Bounding contours show the 0.5, 1, 1.5, 2 contours of the density of points. The olive points are individual quasars from the SDSS sample which satisfy . Overplotted in pink are the quasars contributing to the composite presented here. The quasar colors have been marginalized over in the right side where the tall pink lines are at the position of the composite quasars and the olive shaded area is the kernel density estimation of the distribution of quasars fulfilling the selection criteria. The gray-shaded area is the projection of the