While the selection strategy and ligand encoding have a strong effect on the accuracy of the models, the AL procedure appears to be robust with regards to the initial conditions. When starting with disparate ligand selections from localized chemically similar molecule clusters, the final models converge to comparable final predictions (Fig ). This is encouraging, as in practical applications it may be convenient to initialize the AL cycle from the chemically similar congeneric series of compounds with experimentally readily measured affinities.