To seek the further objective evaluation, three external test sets in the recent work of Dagan-Wiener et al. (2017) are employed accordingly. For the “Bitter New” dataset with 23 bitterants, the prediction accuracies are 74, 74, and 100% for bitterX, BitterPredict, and e-Bitter respectively, while F1-scores are 0.85, 0.85, and 1.00 for bitterX, BitterPredict, and e-Bitter respectively (Table 2). Thus, all the consensus models and average models in the e-Bitter afford the best performance for this dataset (Figure 4 and Table 2).