ΔG° is estimated from the BPMFs by the minimum (min) or exponential average (exp). BPMFs are estimated by the minimum interaction energy (min Ψ), the mean interaction energy (mean Ψ), or using the MBAR estimator. For comparison, using the minimum BPMF, the AUC and AUlC of DOCK 6 are 0.53 (0.05) and 0.15 (0.03), respectively. Using the exponential average of the BPMF is, they are 0.50 (0.05) and 0.13 (0.03). Errors were estimated by bootstrapping: the standard deviation of the AUC or AUlC based on 100 sets of n free energy estimates randomly sampled with replacement from the original n free energy estimates.