표 2. 음성 변수 Table 2. Acoustic categories and their variables

Categories	Variables
Fundamental frequency	F0, STD, PER
Frequency perturbation	Jitt, Jita, RAP, vF0
Amplitude perturbation	ShdB, Shim, vAm
Noise	NHR, VTI

F0, average fundamental frequency; STD, standard deviation of F0; PER, pitch periods; Jitt, jitter percent; Jita, absolute jitter; RAP, relative average perturbation; vF0, F0 variation; ShdB, shimmer in dB; Shim, shimmer percent; vAm, peak amplitude variation; NHR, noise to harmonic ratio; VTI, voice turbulence index.