Table 5. Parameters, standard errors, and performance metrics of biomass allometric equations based on the power function model for the herb group by independent variables.

Independent variable	Parameters			SEE^a	Adjusted R²	RMSE^b	MBE^c
Independent variable	α	β₁	β₂	SEE^a	Adjusted R²	RMSE^b	MBE^c
Nstem^d	0.0882	1.2956	-	0.9027	0.3805	0.2863	0.0033
Lstem^e	0.0074	1.0656	-	0.7498	0.4535	0.2689	−0.0160
H^f	0.0283	0.7572	-	0.8813	0.2394	0.3172	−0.0173
NstemㆍLstem	0.0092	0.8711	-	0.6380	0.7168	0.1936	−0.0062
NstemㆍH	0.0255	0.6866	-	0.7751	0.4807	0.2621	−0.0148
Nstem, Lstem	0.0090	0.8439	0.8853	0.6422	0.7124	0.1937	−0.0061
Nstem, H	0.0292	0.9444	0.5778	0.7692	0.5174	0.2510	−0.0077

SEE: Standard error of estimate
RMSE: Root mean squared error
MBE: Mean bias error
Nstem: Number of stems
Lstem: Length of main stem
H: Height.