Leaf area index estimation model for UAV image hyperspectral data based on wavelength variable selection and machine learning methods

Table 2 Regression analysis of characteristic bands and winter wheat LAI

Modeling method	Variable extraction	Wavelengths numbers	Calibration			Validation
Modeling method	Variable extraction	Wavelengths numbers	R²	RMSE	RPD	R²	RMSE	RPD
PLSR	Full_spectrum	94	0.79	0.81	2.15	0.78	0.79	2.06
	FD	4	0.81	0.77	2.26	0.81	0.75	2.15
	SPA	28	0.79	0.81	2.14	0.78	0.81	2.01
	CARS	13	0.80	0.79	2.22	0.81	0.78	2.08
	CARS_SPA	9	0.83	0.73	2.39	0.83	0.74	2.19
SVR	Full_spectrum	94	0.80	0.79	2.20	0.77	0.79	2.06
	FD	4	0.80	0.78	2.22	0.80	0.72	2.24
	SPA	28	0.81	0.75	2.31	0.79	0.76	2.14
	CARS	13	0.79	0.79	2.20	0.77	0.79	2.04
	CARS_SPA	9	0.82	0.75	2.31	0.84	0.65	2.75
Xgboost	Full_spectrum	94	0.93	0.50	3.48	0.80	0.79	2.04
	FD	4	0.88	0.65	2.69	0.81	0.75	2.17
	SPA	28	0.84	0.73	2.37	0.76	0.82	1.96
	CARS	13	0.82	0.82	2.12	0.82	0.84	1.93
	CARS_SPA	9	0.89	0.63	2.51	0.89	0.55	2.92

ISSN: 1746-4811