To sum up, most heatmaps and the corresponding FPA overlaps are relatively insensitive to the training set size and the results are close to converged for a training set size of 1000 molecules, although for molecules with low overlap some heatmaps change significantly. The difference in average error for molecules with high and low overlap is more pronounced for smaller training sets (Figure ), but this could just reflect the larger spread in errors for models trained on smaller training sets.