Distribution in terms of M_*, L_X/M_*, and redshift for XMM-COSMOS AGN with known spec-z (left panels) and spec-z + phot-z Pdfs (right panels). The low and high M_* subsamples are created so that they have exactly the same specific BH accretion rate distribution (upper panels). A similar approach is used in terms of specific BH accretion rate (lower panels). For clarity, when the histograms match exactly, we have slightly offset the bins visually for the high subsample.