Fig. 4. Fitting effects of the (a) CatBoost, (b) XGBoost, and (c) GBR model-predicted and true work functions on the test set. Individual SHAP plots of the CatBoost model predictions for (d) Br₆Sb₂, (e) Mo₂Te₄, and (f) Au₂Br₄. The SHAP positive (red) and negative (blue) feature weights are given for the three materials. The bar size represents the SHAP value. The base value is the mean value of the work function in the training data. The output value f(x) represents the predicted work function of the three materials.