Luminosity vs. redshift distribution. The red kernel density estimate plot represents the red eHAQ+GAIA23 quasar distribution, and each purple dot represents a radio-detected red quasar. The black circles represent red BAL quasars. In addition to these markers, the blue kernel density estimate plot shows the blue SDSS DR7 quasars. Center: logarithm of the rest-frame 6 μm luminosity of either all the blue SDSS quasars (a) or the redshift–luminosity matched blue SDSS quasars (b) in blue curves and the red eHAQ+GAIA23 quasars in red curves as a function of redshift, assuming a continuous probability density curve. Top: density histogram of the redshift for the two different populations. Right: density histogram of the rest-frame 6 μm luminosity for the two different populations.