Although the four properties contribute appreciably to the predicted ℎ .# , two of them are by far the most important, with similar weights both for the training and test groups. The importance of electron delocalization in the aromatic ring for predicting ℎ .# was found before by us and others. However, the importance of the magnitude of the total dipole moment of the explosophore nitro(s) group(s) was not identified before by us or the literature -its contribution in the test group (35%) is similar to the electron delocalization (39%). This is chemically justified because the dipole moment measures the polarization of the explosophore 𝑁𝑂 ' that affects the ring electrons and, accordingly, its 𝐶 -𝑁𝑂 ' bond strengths, thus characteristics of electronic structure of the molecule that are relevant for the sensitivity. We found that the charge of the nitro group contributes far less (16%), although, in other works, they were treated as the sole molecular contributor to ℎ .# . The test group included 11 molecules with a wide range of sensitivity (ℎ .# ) values, varying from very sensitive (PTETNT, ℎ .# = 25 cm) to highly insensitive (DATB, ℎ .# = 320 cm). Table The RMSE values of the test set for each algorithm and the previous results of the same molecules are presented in Fig. . In the previous work, the 21 The SHAP plots in Fig. present the results for each molecule that produced the average information of Tables and. The ordering in the vertical axis indicates that the higher the property, the higher is its contribution to the final ℎ . A clear and very interesting pattern emerges from these plots in Fig. . The 11 molecules of the test group can be divided into three groups according to the values of ℎ .# and the direction of the contributing properties. For the most sensitive explosives (ℎ .# value between parentheses), PTETNT (25 cm), TETNB (28 cm) and PATETNT (47 cm), the four molecular properties contribute to reducing the ℎ .# value (i.e., they are in blue). According to AdaBoost results, which are similar to the one obtained with the other algorithms, the polarization of the nitro groups (∑ 𝑄 * (𝑁𝑂 ' )), followed by the electron delocalization of the ring atoms (∑ 𝑄 ' (𝐶)), are the two most important properties in this group by far. For the second group comprised of TNBEtOH (68 cm), DCLTNAN (75 cm), TNT (98 cm), DNB (100 cm), TMTNB (110 cm), and DATNP (112 cm), two properties contribute to increasing ℎ .# (i.e., they are in red) and two to reducing it (i.e., they are in blue). The number of nitro groups (#𝑁𝑂 ' ), and with a more significant contribution, the polarization of the nitro groups, contribute to increasing ℎ .# , whereas the other two properties (most importantly ∑ 𝑄 ' (𝐶), and the charge of the nitro groups, ∑ 𝑄 # (𝑁𝑂 ' ))