Top: all of our sample objects plotted in α _ox–L _{2500 Å} space. The objects from Timlin et al. (2020a) are shown as circles, our Chandra/HST objects as triangles, the median values for the SDSS-RM targets from Rivera et al. (2020) as stars, and the Lusso et al. (2020) objects as squares. The Chandra/HST and Nardini et al. (2019) objects are highlighted in black to illustrate the samples with a small range of luminosity. Bottom: all values of α _ox and L _{2500 Å} calculated for the SDSS-RM objects. The colored tracks indicate the variability in L _{2500 Å}. The best fit from Timlin et al. (2020a) is shown as the solid black line; the dotted line shows the boundary for X-ray-weak quasars with Δα _ox values < = −0.2. The points in both panels are colored by the C IV ∥ distance. The plus sign in the lower right corner in the bottom panel shows the median errors for the SDSS-RM sample.