Table 2: Validation results of the models.

No. Models Input Variables Used RMSE MAE R
1 Model 1 X1, X2, X3 0.514 0.404 0.725
2 Model 2 X1, X2, X4 0.437 0.337 0.822
3 Model 3 X1, X4, X5 0.573 0.462 0.715
4 Model 4 X1, X6, X7 0.644 0.512 0.723
5 Model 5 X1, X2, X3, X4, X5 0.444 0.332 0.820
6 Model 6 X1, X2, X3, X6, X7 0.477 0.365 0.787
7 Model 7 X2, X3, X4 0.571 0.422 0.668
8 Model 8 X1, X2, X4 0.441 0.354 0.815