A comparison of four vowel overlap measures

Area of Science:

• * Phonetics and Acoustics
• * Speech Science
• * Auditory Perception

Background:

• * Vowel overlap measures quantify acoustic differences between vowel sounds.
• * Existing metrics like SOAM, APP, VOACH, and Pillai score vary in their approach.
• * Understanding vowel overlap is crucial for speech analysis and linguistic research.

Purpose of the Study:

• * To theoretically critique and empirically assess four prominent vowel overlap measures.
• * To determine the most accurate and precise metric for quantifying vowel overlap.
• * To highlight the utility of robust vowel overlap measures in phonetic research.

Main Methods:

• * Theoretical analysis of four vowel overlap metrics: SOAM, APP, VOACH, and Pillai score.
• * Empirical assessment using Monte Carlo simulations with accuracy and precision criteria.
• * Comparison of spectral and durational acoustic features (F1, F2).

Main Results:

• * Theoretical critique favors the a posteriori probability (APP)-based metric and Pillai score over SOAM and VOACH.
• * Monte Carlo simulations indicate the Pillai score exhibits superior performance.
• * The Pillai score demonstrated the highest accuracy and precision in empirical tests.

Conclusions:

• * The Pillai score is recommended as the preferred metric for quantifying vowel overlap.
• * Robust vowel overlap measures are essential for comparative phonetic studies and formant trajectory analysis.
• * Findings support the application of advanced acoustic analysis in sociolinguistics and phonetics.