Self-prediction test using full features as indicated in Table 1, with the full-counts training sample incorporating added measurement errors, as described in Sect. 2.2.2. Top row: target is M_DM(r_1/2). Bottom row: target is M_tot(r_1/2). The results without measurement errors are presented in Appendix B. The data is divided into 80% for training and 20% for testing. The x-axis represents the true values, while the y-axis represents the predicted values. “numofgal” is the number of the test set. The purple error bar represents the 16%, 50%, 84% percentiles as a function of M^true(r_1/2), with a bin size of 0.2 dex. The red dashed line is ±0.30 dex (corresponding to ∼2σ errors, see text). Outliers are defined as the fraction of data outside the red dashed line. In the case of accurate predictions, the data points are expected to lie along the dotted 1-to-1 line.