Self-prediction test of the MELA_ALL is performed using the full set of the features, and the M_tot(r_1/2) as the target. As explained in Sect. 3.2, for this test the training utilizes balanced-counts training samples. These training samples comprise 21 000 × 80% = 16 800 galaxies for each class (i.e., dETGs, nETGs, LTGs), accompanied by 4200 galaxies for testing. The predictions of the entire TNG sample are presented as the self-prediction test in Fig. 5.