Table 2.
Dysphonia features.
| Classification and dysphonia features | Description | |
| Pitch [18] (fundamental frequency) |
|
|
|
|
F0_mean | Mean of pitch |
|
|
F0_max | Max of pitch |
|
|
F0_min | Min of pitch |
|
|
F0_median | Median of pitch |
|
|
F0_std | SD of pitch |
| Jitter [18] (pitch period perturbation) |
|
|
|
|
Jitter | Jitter |
|
|
Jitter_abs | Absolute jitter |
|
|
Jitter_PPQ5 | 5 adjacent points’ jitter |
|
|
Jitter_rap | 3 adjacent points’ jitter |
|
|
Jitter_ddp | Difference of 3 adjacent points’ jitter |
| Shimmer [18] (amplitude perturbation) |
|
|
|
|
Shimmer | Shimmer: percentage |
|
|
Shimmer_dB | Shimmer: decibels (dB) |
|
|
Shimmer_APQ5 | 5 adjacent points’ shimmer |
|
|
Shimmer_APQ3 | 3 adjacent points’ shimmer |
|
|
Shimmer_dda | Difference of 3 adjacent points’ shimmer |
|
|
Shimmer_APQ11 | 11 adjacent points’ shimmer |
| Harmonics-to-noise ratio (HNR) and noise-to-harmonics ratio (NHR) [19] |
|
|
|
|
HNR_mean | Mean of HNR |
|
|
HNR_std | SD of HNR |
|
|
NHR_mean | Mean of NHR |
|
|
NHR_std | SD of NHR |
| Nonlinear feature |
|
|
|
|
DFA | Detrended fluctuation analysis [20] |
|
|
RPDE | Recurrence period density entropy [21] |
|
|
D2 | Correlation dimension [22] |
|
|
PPE | Pitch period entropy [23] |