To assess the importance of the functional form of the model, we also apply the thermodynamic features in both ridge regression and random forest ML models (Figures and, respectively) and compare the results (Tables and) to the thermodynamic model (Figure . The ridge regression also shows the relative importances of the thermodynamic features and how they differ between the quinone and hydroquinone models (Table ). In the hydroquinone ridge regression model, one of the most predictive features is the molecular volume, V m and T m , which is consistent with the positive weight in the ridge regression model.