As mentioned in Section II C, we do not actually screen the two-body interactions in this work, and instead evaluate all of the one-and two-body terms at the target level of theory. (This means one fewer parameter to test in the present work, and two-body screening can easily be incorporated later.) The graph in Fig. (a) is intended as a schematic to illustrate that within the top-down approach, any sparsity that may be obtained via screening at the n-body level does not propagate downward, mean-ing that all of the (n -1)-body terms must be screened. This is true for higher-order interactions as well, beyond the n = 3 case that is illustrated in Fig. .