Table 10. MCC of the best pairs of features for wheeze and normal sound classification using logistic regression on the Test-Set.
| First Feature | Second Feature | MCC |
|---|---|---|
| Tonality index | Spectral slope | 0.7161 |
| Tonality index | MFCC-1 | 0.7154 |
| Tonality index | Entropy ratio | 0.7142 |
| Spectral slope | f25/f90 | 0.7053 |
| MFCC-1 | MFCC-2 | 0.6981 |
| Entropy difference | Spectral Irregularity | 0.6933 |
| Tonality index | MFCC-8 | 0.6849 |
| Spectral crest factor | Spectral Irregularity | 0.6849 |
| Spectral slope | MFCC-2 | 0.6823 |
| Tonality index | Averaged PSD-7 | 0.6822 |
| Tonality index | Renyi entropy | 0.6811 |
| Tonality index | MFCC-11 | 0.6788 |
| Tonality index | - | 0.5790 |
| f25/f90 | - | 0.5420 |