[Retracted] Prediction Mathematic Model and Influencing Factors of Contact Stress of Cylindrical Gear with Arc Tooth

Table 3

Evaluation indexes before and after optimization.

Indexes	Kriging	WOA-Kriging	Optimization effect (%)
R^2	0.9922	0.9974	0.52
RMSE	2.8569	1.6540	42.11
RMAE	0.1322	0.0754	42.97