Performance as function of limiting magnitude. All objects brighter than the magnitude cut in the r band are considered to compute the f₁ score. Blue solid lines show the f₁ score as defined in Eq. (1), and the orange dashed lines show the more relaxed statistic (see text for details). Green dotted lines show the confidence threshold used to compute the f₁ score. From top to bottom, we show results for the test sample (Sect. 4.1), the 1 deg² test sample (Sect. 4.2), and the SDSS cross-match sample (Sect. 4.3). We note that in the bottom panels, the lines stop at magnitude 23.4; the sample does not have fainter objects.