Data balance (protein) = Proportion of actives (protein) = n_active_compounds n_total_compounds Thus, a comprehensive analysis of data balance was carried to better understand and interpret performance results. For each of the balancing strategies, the original distribution of active ratios per protein was characterized. We also compared the original imbalance of the training and test sets for each strategy to explore possible trends, and studied the effect that other covariates (the protein length and the number of interactions of each protein in its corresponding set and fold) might have on the original test set imbalance.