From: Estimation of nitrate nitrogen content in cotton petioles under drip irrigation based on wavelet neural network approach using spectral indices
Spectral index type
Modeling
Validation
Number of samples
R2
RSME (g/L)
MAE (g/L)
Vegetation indices
60
0.81
0.91
0.73
0.82
0.87
0.68
Blue edge parameters
0.88
0.74
0.58
0.65
0.47