Three IL (Bis4MPyC6, Bis2MPyC9, Hex4MPy) and two polymeric SP: polyethylene glycol and 5%phenyl-methylpolysiloxane were considered. MD selected for Bis4MPyC6 and Bis2MPyC9 are very similar to each other. This is consistent with the fact that these IL are very close in their chemical nature. However, Bis4MPyC6 is more polar, consequently the RI values are higher (the data set consisted of polar molecules) and the absolute values of the coefficients in the LASSO regression before MD are higher. Thus, the PEOE_VSA7 descriptor characterizes the accessible surface of atoms which Gasteiger charge is in the range [-0.05; 0]. Such charges typically have aromatic carbon and other atoms in moderately polar groups, while aliphatic carbons are hidden by positive-charged hydrogens. The BCUT2D_LOGPLOW is the lowest eigenvalue of a matrix which diagonal elements contain contributions of atoms to LogP (factor of lipophilicity) and non-diagonal elements contain information about the connectivity between the corresponding atoms. Both MD are topological and related to the polarity of the molecule, and the average coefficients before them increase with the polarity of the molecule. It should be noted that the most influential according to different MD selection methods fr_benzene (the number of benzene rings) and PEOE_VSA7 are not strongly correlated: the Pearson correlation coefficient is ~0.5 for the considered data set. The topological chi1 descriptor is higher for linear molecules and lower for branched ones and characterizes the shape of the molecule. in structure, and the set of selected MD also significantly differs. Thus, despite all the above notes that the MD selection is not reproducible when the data set is changed, it is possible to compare SP using QSRR. Polymeric SP are even more different compared with IL-based SP. For Bis4MPyC6 and Bis2MPyC9, the fr_benzene descriptor was selected with a very high probability by the SEQ_ADD method, it is the MD that is the most correlated with RI. For Hex4MPy, it is much less significant according to the same method. The tendency continues with less polar PEG. As for siloxane, it is absent in the top 10. As expected, the polar and aromatic Bis4MPyC6 and Bis2MPyC9 are the most sensitive to aromatic systems.