5.3.1. Influence of Number of Rules (nrule)

5.3.1. Influence of Number of Rules (nrule) The evaluation of RMSE, MAE, R, and IA in the function of nrule is presented in Figure 8a–d, respectively, for both training and testing parts. It can be seen that the accuracy of the ANFIS-PSO reduced when the number of nrule increased (i.e., RMSE and MAE increased, while R and IA The evaluation of RMSE, MAE, R, and IA in the function of nrule is presented in Figure 8a–d, respectively, for both training and testing parts. It can be seen that the accuracy of the ANFIS-PSO reduced when the number of nrule increased (i.e., RMSE and MAE increased, while R and IA decreased). It is worth noting that the higher the number of rules, the larger dimensionality of the problem

decreased). It is worth noting that the higher the number of rules, the larger dimensionality of the problem (Figure 2). Therefore, regarding the total number of ANFIS weight parameters, the

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Figure 8. Evaluation of statistical criteria in the function of nrule: (a) RMSE, (b) MAE, (c) R, and (d) IA. **Figure 8.** Evaluation of statistical criteria in the function of nrule: (**a**) RMSE, (**b**) MAE, (**c**) R, and (**d**) IA.
