TABLE 2.

Performance of models in test and train sets.

Models		Train error	MSE	Numbers of selected features
LR	Diameter of C	1.41	4.81	30
	Diameter of D	0.84	2.54	28
	Diameter of E	0.73	2.52	22
SVM	Diameter of C	2.68	1.86	34
	Diameter of D	1.41	1.82	37
	Diameter of E	1.48	1.91	38
ETR	Diameter of C	3.28 × 10–29	2.43	25
	Diameter of D	3.24 × 10–29	2.04	21
	Diameter of E	2.49 × 10–29	2.34	17
RFR	Diameter of C	3.85	2.51	20
	Diameter of D	2.30	2.73	17
	Diameter of E	2.08	3.00	15

LR, linear regression. SVM, support vector regression. ETR, extra-tree regression. RFR, random forest regression.