Prediction of Mechanical Properties of Aluminium Alloy Strip Using the Extreme Learning Machine Model Optimized by the Gray Wolf Algorithm

Table 7

Comparison of the predictive performance of the three models.

Mechanical properties	Name	RMSE		MAPE		R^2
		Train set	Test set	Train set	Test set	Train set	Test set
Tensile strength	GWO-ELM	9.052	5.365	1.951	1.703	0.9549	0.9857
	MGWO-ELM	7.939	11.557	1.574	2.316	0.9534	0.9805
	ELM	10.976	21.489	2.702	5.317	0.9386	0.7102
Yield strength	GWO-ELM	15.499	11.881	4.204	2.703	0.9303	0.9662
	MGWO-ELM	16.795	20.465	4.225	5.185	0.9022	0.9804
	ELM	19.163	43.313	6.176	16.165	0.9053	0.3958
Elongation	GWO-ELM	1.424	1.268	7.371	5.994	0.7649	0.9141
	MGWO-ELM	1.355	1.845	6.937	9.244	0.8123	0.9074
	ELM	1.630	5.360	8.864	19.630	0.7384	−0.8312