Table 4.

Outer-fold predictive performance of different models in predicting Y under nested grouped cross-validation.

Model	R²	RMSE (kN)	MAE (kN)	MAPE (%)
Support Vector Regressor	0.737	4102.71	2111.74	30.51
Random Forest Regressor	0.984	1015.16	538.15	8.95
Gradient Boosting Regressor	0.962	1560.01	899.61	24.03
DNN	0.998	362.83	253.07	6.61