Table 2 Classification parameters obtained for PLS-DA model of the inner part samples with different collection regions.
Parameters | Inner part | ||||||||
|---|---|---|---|---|---|---|---|---|---|
BS | CX | HH | LC | NJ | PE | WS | YX | Average | |
Calibration set | |||||||||
  Sensitivity (%) | 100.00 | 100.00 | 92.86 | 100.00 | 100.00 | 96.00 | 100.00 | 93.55 | 97.80 |
  Specificity (%) | 96.55 | 96.23 | 97.25 | 96.43 | 96.55 | 96.94 | 96.43 | 97.83 | 96.77 |
  Efficiency (%) | 98.26 | 98.10 | 95.03 | 98.20 | 98.26 | 96.47 | 98.20 | 95.66 | 97.27 |
  MCC | 0.78 | 0.88 | 0.85 | 0.84 | 0.78 | 0.90 | 0.84 | 0.91 | 0.85 |
  Accuracy (%) | 96.75 | 96.75 | 96.75 | 96.75 | 96.75 | 96.75 | 96.75 | 96.75 | 96.75 |
Validation set | |||||||||
  Sensitivity (%) | 100.00 | 100.00 | 100.00 | 80.00 | 66.67 | 100.00 | 100.00 | 92.86 | 92.44 |
  Specificity (%) | 93.88 | 93.18 | 93.48 | 95.74 | 95.92 | 92.86 | 93.75 | 94.74 | 94.19 |
  Efficiency (%) | 96.89 | 96.53 | 96.68 | 87.52 | 79.97 | 96.36 | 96.82 | 93.79 | 93.07 |
  MCC | 0.69 | 0.82 | 0.79 | 0.70 | 0.55 | 0.85 | 0.73 | 0.86 | 0.75 |
  Accuracy (%) | 94.23 | 94.23 | 94.23 | 94.23 | 94.23 | 94.23 | 94.23 | 94.23 | 94.23 |
  RMSEE | 0.11 | 0.15 | 0.17 | 0.14 | 0.12 | 0.16 | 0.17 | 0.21 | 0.15 |
  RMSECV | 0.16 | 0.24 | 0.25 | 0.20 | 0.20 | 0.26 | 0.23 | 0.32 | 0.23 |
Permutation test | |||||||||
  R2 (min-max) | 0.16–0.45 | 0.17–0.47 | 0.14–0.47 | 0.18–0.47 | 0.13–0.45 | 0.19–0.47 | 0.17–0.45 | 0.22–0.49 | — |
  Q2 (min-max) | −1.98–−0.35 | −2.23–−0.49 | −2.17–−0.49 | −1.96–−0.32 | −2.01–−0.27 | −2.26–0.44 | −2.24–−0.36 | −2.37–−0.53 | — |
  R2-intercept | 0.33 | 0.35 | 0.36 | 0.34 | 0.33 | 0.38 | 0.35 | 0.39 | 0.35 |
  Q2-intercept | −1.09 | −1.27 | −1.19 | −1.10 | −1.05 | −1.42 | −1.12 | −1.44 | −1.21 |
