Table 2.
Results of regression models for the quantification of Notoginseng powder (NP) adulterated by sophora flavescens powder (SFP), corn flour (CF), and the mixture of two adulterants using least-squares support vector machines (LS-SVM) algorithm based on the data of visible spectra, short-wave near infrared spectra (SNIR), and long-wave near infrared spectra (LNIR), respectively.
| Adulterant | Spectral Range | Modeling Method | LVs | Calibration | Prediction | ||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
|
|
||||||||||
| rC |
|
RMSEC (%) | rP |
|
RMSEP (%) | RPD | |||||
| SFP | Visible | LS-SVM | / | 0.971 | 0.943 | 1.693 | 0.932 | 0.846 | 2.778 | 2.670 | |
| PLSR | 6 | 0.939 | 0.882 | 2.427 | 0.911 | 0.787 | 3.261 | 2.314 | |||
| SNIR | LS-SVM | / | 0.961 | 0.922 | 1.972 | 0.921 | 0.841 | 2.815 | 2.559 | ||
| PLSR | 4 | 0.867 | 0.751 | 3.528 | 0.874 | 0.762 | 3.451 | 2.055 | |||
| LNIR | LS-SVM | / | 0.984 | 0.967 | 1.276 | 0.917 | 0.840 | 2.829 | 2.501 | ||
| PLSR | 4 | 0.924 | 0.853 | 2.709 | 0.912 | 0.821 | 2.994 | 2.362 | |||
| CF | Visible | LS-SVM | / | 0.950 | 0.897 | 2.269 | 0.845 | 0.710 | 3.809 | 1.858 | |
| PLSR | 10 | 0.936 | 0.876 | 2.489 | 0.792 | 0.602 | 4.461 | 1.623 | |||
| SNIR | LS-SVM | / | 0.994 | 0.987 | 0.796 | 0.959 | 0.918 | 2.029 | 3.514 | ||
| PLSR | 5 | 0.851 | 0.724 | 3.716 | 0.821 | 0.670 | 4.062 | 1.746 | |||
| LNIR | LS-SVM | / | 0.986 | 0.973 | 1.166 | 0.930 | 0.864 | 2.609 | 2.724 | ||
| PLSR | 5 | 0.957 | 0.916 | 2.047 | 0.946 | 0.893 | 2.308 | 3.071 | |||
| SFP&CF | Visible | LS-SVM | / | 0.834 | 0.685 | 3.241 | 0.688 | 0.471 | 4.198 | 1.376 | |
| PLSR | 2 | 0.548 | 0.300 | 4.830 | 0.574 | 0.327 | 4.735 | 1.220 | |||
| SNIR | LS-SVM | / | 0.996 | 0.991 | 0.555 | 0.786 | 0.560 | 3.830 | 1.577 | ||
| PLSR | 1 | 0.576 | 0.332 | 4.720 | 0.571 | 0.325 | 4.743 | 1.218 | |||
| LNIR | LS-SVM | / | 0.892 | 0.794 | 2.621 | 0.898 | 0.789 | 2.652 | 2.183 | ||
| PLSR | 8 | 0.887 | 0.787 | 2.665 | 0.871 | 0.754 | 2.862 | 2.033 | |||
LVs: Number of latent variables.