. 2019 Jul 9;9(7):430. doi: 10.3390/ani9070430

Table 2.

Fitting statistics of prediction models for milk minerals and ratio between micellar and diffusible fractions (w/w) in cross-validation obtained using partial least squares (PLS) and backward interval PLS (BiPLS) analysis (n = 91).

Trait		PLS				BiPLS					ΔR²_CV
Trait		LV	RMSE_CV	R²_CV	RPD_CV	NV	LV	RMSE_CV	R²_CV	RPD_CV	ΔR²_CV
Ca	Total, mg/100 mL	9	5.86	0.68	1.76	230	10	4.77	0.79	2.16	0.11
	Diffusible, mg/100 mL	5	3.15	0.69	1.79	180	9	2.69	0.77	2.09	0.08
	Micellar, mg/100 mL	8	6.35	0.66	1.70	160	10	5.30	0.76	2.04	0.10
	Micellar/Diffusible, w/w	5	0.58	0.52	1.45	90	6	0.36	0.69	1.78	0.17
P	Total, mg/100 mL	5	5.58	0.62	1.62	100	10	3.30	0.87	2.73	0.25
	Diffusible, mg/100 mL	7	2.91	0.64	1.67	230	10	2.56	0.73	1.90	0.09
	Micellar, mg/100 mL	5	6.27	0.52	1.43	210	10	4.76	0.73	1.89	0.21
	Micellar/Diffusible, w/w	7	0.27	0.56	1.49	220	10	0.22	0.68	1.77	0.12
K	Total, mg/100 mL	10	8.58	0.35	1.24	100	10	7.14	0.55	1.49	0.20
	Diffusible, mg/100 mL	6	7.58	0.49	1.40	100	9	6.92	0.58	1.53	0.09
	Micellar, mg/100 mL	7	8.69	0.18	1.08	180	7	8.19	0.25	1.15	0.07
	Micellar/Diffusible, w/w	3	0.09	0.09	1.04	90	7	0.08	0.29	1.17	0.20
Mg	Total, mg/100 mL	7	0.74	0.57	1.52	140	10	0.64	0.68	1.76	0.11
	Diffusible, mg/100 mL	5	0.62	0.43	1.32	190	7	0.54	0.57	1.52	0.14
	Micellar, mg/100 mL	5	0.68	0.48	1.38	160	7	0.53	0.68	1.77	0.20
	Micellar/Diffusible, w/w	4	0.16	0.33	1.22	140	6	0.13	0.56	1.51	0.23
Na	Total, mg/100 mL	8	4.85	0.63	1.64	290	10	4.02	0.75	1.98	0.12

Na was not found in micellar phase and thus it is presented as total Na only. Abbreviations are as follows: LV, number of latent variables for calibration; RMSE_CV, root mean square error in cross-validation; R²_CV, coefficient of determination in cross-validation; RPD_CV, ratio of performance to deviation in cross-validation; NV, number of spectral variables selected in the model; ΔR²_CV, difference between R²_CV of BiPLS and PLS.