Table 1.
Confusion matrix computed from the PLS-DA model of Raman spectra collected from four watermelon cultivars.
| Ripening stage | Total spectra | Predicted as A | Predicted as B | Predicted as C | Predicted as D | Correct (%) |
|---|---|---|---|---|---|---|
| Fascination | ||||||
| A | 43 | 38 | 5 | 0 | 0 | 88.4 |
| B | 42 | 8 | 27 | 7 | 0 | 64.3 |
| C | 42 | 2 | 11 | 27 | 2 | 64.3 |
| D | 24 | 0 | 0 | 1 | 23 | 95.8 |
| Orange crisp | ||||||
| A | 43 | 40 | 1 | 2 | 0 | 93.0 |
| B | 43 | 0 | 43 | 0 | 0 | 100 |
| C | 39 | 4 | 1 | 32 | 2 | 82.1 |
| D | 40 | 0 | 0 | 0 | 40 | 100 |
| Amarillo | ||||||
| A | 42 | 42 | 0 | 0 | 0 | 100 |
| B | 42 | 12 | 27 | 3 | 0 | 64.3 |
| C | 42 | 0 | 3 | 38 | 1 | 90.5 |
| D | 20 | 0 | 0 | 0 | 20 | 100 |
| Crimson sweet | ||||||
| A | 42 | 36 | 6 | 0 | 0 | 85.7 |
| B | 42 | 9 | 31 | 2 | 0 | 73.8 |
| C | 42 | 1 | 4 | 37 | 0 | 88.1 |
| D | 20 | 0 | 0 | 0 | 20 | 100 |
Bold value is the highest number of spectrums predicted according to their ripening stage.