Comparison of the ‘true’ (M_G, true) and predicted (M_G, pred) absolute magnitude for the stars of the training sample. Left panel: the true and derived quantities plotted against each other. The one-to-one relation is shown as a solid line, and the dashed and dotted lines correspond to the 1 − σ and 2 − σ deviations, respectively. Right panel: the distribution of the difference between the true and derived absolute magnitude, with a Gaussian fit overlaid. A scatter of 0.27 mag corresponds to a relative uncertainty on the distance of 13%.