In order to identify a descriptor that can appropriately capture the activity towards CO oxidation for the 13 ABO3 (A = La, Pr, Nd, Sm; B = Cr, Mn, Fe, Co) materials, we applied the SISSO approach. This method identifies models of a target of interest W (YZYY[) as analytical expressions containing key parameters, out of many offered primary features. SISSO was used to derive, for instance, a tolerance factor indicating the perovskite stability that is more accurate than the Goldschmidt tolerance factor. In this paper, the target that we will model is ? @A .