Table 2.
Effect of peak selection signal to noise ratio (S/N) on classification
| I | II | III | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| S/N | Peaks | I | II | III | I | II | III | I | II | III |
| % spectra | ||||||||||
| 1 | 6 | 2 | 37 | 60 | 19 | 23 | 58 | 6 | 15 | 79 |
| 2 | 5 | 4 | 23 | 73 | 27 | 20 | 53 | 8 | 10 | 82 |
| 4 | 8 | 3 | 13 | 84 | 25 | 7 | 68 | 9 | 8 | 83 |
| 6 | 2 | 2 | 2 | 95 | 12 | 12 | 76 | 6 | 6 | 89 |
Classification is sensitive to the signal-to-noise ratio used in selecting peaks. The experiment in Table 1 was repeated under various ratios to illustrate the effect on number of peaks used in the classifier and subsequent totaled classification represented in percentages of total image spectra classified within each MSI class.