The net force error across all models are very similar for all mappings. Even with a more complex representation of the PES and training directly on forces, the ML and TL models show negligible improvement in mean force errors (Fig. ). This flat trend strongly suggests that the irreducible error associated with dimension reduction dominates the force error rather than the representability limitations of the models. To further investigate this hypothesis we histogrammed the atomistic force components on each bead and compared them with the force components predicted by each CG model (Fig. ). The average values within each histogram bin over all beads and configurations are shown in Figure for distinct scenar-ios.