Residual X-ray luminosity, after normalization with the M – L_X and M – Ṁ relations, as a function of the mass accretion rate. Left figures correspond to the Hα subsample. Right figures correspond to the U-excess subsample. The top plots present the results using the OLS method for the initial regression analyses between M_∗, L_X and Ṁ_acc. The bottom ones when using the outlier rejection method for those same analyses. Regression lines (straight), with their respective errors in the slope (shaded areas), are shown for the OLS (black) and outlier rejection (red) final regression results.