Ratio between X-ray and G-band fluxes as a function of the associated Gaia object’s BP-RP color. The objects are colored according to the parallax. The label in the lower part of all seven panels indicate in which sample the colored objects belong: SVM, Bayes, and Salvato describe the method and “!” equals not, that is, that the colored identification are not identified by the method that is preceded by the “!”. The number in bracket indicates the respective number of sources. In rows two and three, the gray dots represent the objects of the top panel for reference. The dotted line in the bottom row indicates log L_X/L_bol = −2.5.