We now check a rather important parameter for generative models -variation . For an algorithm like SPOT-LIGHT that does not parallelly optimize too many properties of the molecules, a reasonable variation among the molecules is helpful as it allows at least some molecules to have multiple favorable properties other than just strong protein binding. We use the self-similarity distribution (SSD) as a mea-FIG. : Similarity to the nearest neighbor in the same set before any reinforcement. The mean similarity is 0.39 ± 0.004. sure of variability. The SSD is the distribution of selfsimilarity (SS) of a set of size N , defined as follows.