Table 2.

The statistical parameters of developed GPRs.

	R2	MRE (%)	MSE	RMSE	STD
GPR (rational quadratic)
Train	0.987	4.08134	0.00005	0.00707	0.00471
Test	0.983	4.67914	0.00004	0.00636	0.00439
Total	0.986	4.22817	0.00005	0.00636	0.00460
GPR (exponential)
Train	0.995	2.82505	0.00002	0.00444	0.00334
Test	0.990	3.82609	0.00003	0.00554	0.00436
Total	0.993	3.07092	0.00002	0.00554	0.00359
GPR (squared exponential)
Train	0.990	3.71123	0.00004	0.00618	0.00475
Test	0.985	3.95804	0.00004	0.00603	0.00419
Total	0.989	3.77185	0.00004	0.00603	0.00458
GPR (matern)
Train	0.997	1.83752	0.00001	0.00335	0.00257
Test	0.994	2.38225	0.00001	0.00370	0.00282
Total	0.996	1.97131	0.00001	0.00370	0.00261