The distribution of Tanimoto similarity of 5-nearest neighbours (NN) was calculated by ECFP4 using the RDKit (version 2020.09.01) 37 Chem functions. We set each bins according to the Tanimoto similarity as less than 0.2, 0.2 to 0.3, 0.3 to 0.4, and more than 0.4 (since lower and larger thresholds were not populated with sufficient numbers of data points) and plotted the percentage of compounds predicted correctly and incorrectly against these bins to investigate whether we can see the applicability domain through the predictivity of models built in this study.