3.4.16 Soil B prediction
Excellent prediction for calibration was obtained using the MARS model (R2c=0.88; MBEc=0.06; RMSEc=4.03; RPDc=2.42) (Figure 4p). Whereas, PCR had the highest and acceptable prediction accuracy (R2p=0.73; MBEp=-1.79; RMSEp=6.12; RPDp=1.74) for validation. Soil B has been predicted with low R2=0.17-0.30 using airborne hyperspectral imaging and laboratory MIR spectroscopy (2500-25000 nm) (Hively et al. , 2011; Janik et al. , 1998). Malmir et al. (2019) reported acceptable prediction accuracy of R2=0.71 with PLSR model to predict soil B using hyperspectral image data in the spectral range of 400-1000 nm.