For the log P and pK a challenge, we list consistently well-performing methods that were ranked in the top consistently according to two error and two correlation metrics: RMSE, MAE, R 2 , and Kendall's Tau. These are shown in Table and For each challenge, we also evaluated the relative difficulty of predicting the physical property of interest of each molecule in the set. We plotted the distributions of errors in prediction for each molecule considering all prediction methods. We also calculated the MAE for each molecule as an average of all methods, as well as for predictions from each method category.