Next, we investigated the conventional ML model to predict Fa and compared its predictivity with that of the GUTFW model. The R 2 value and RMSE in the 10-fold CV and test datasets are shown in Table , and the plot between observed and predicted values is shown in Figure and C. First, in the case of the RF model using AP descriptors as explanatory variables, the R 2 values (0.233) in the 10-fold CV were higher than those in the GUTFW model (0.181), and the RMSE (27.9%) in the 10-fold CV was lower than that in the GUTFW model (37.6%). In the test dataset, the R 2 value (0.339) was lower than that of the GUTFW model (0.353), whereas the RMSE (25.4%) in 10-fold CV was lower than that of the GUTFW model (31.9%). There was no clear tendency of predictivity. In particular, the number of compounds underestimated less than -15%