Table 4. Empirical comparison of the sensitivity of formant frequencies to speech articulation in the simulated and human speech data sets.

The measure presented is normalized standard deviation: $\frac{{\sigma }_{F_n}}{2n-1}$, where n is the formant number. Lower numbers indicate less sensitivity to articulation. Note that sensitivity decreases as higher formants are considered.

Formant #	Simulated Speech Data	Human Speech Data
1	104.0	198.0
2	98.3	102.9
3	97.2	74.7
4	65.1	55.0