This contribution provides a cross-language study on the acoustic and prosodic characteristics of vocalic hesitations.One aim of the presented work is to use large corpora to investigate whether some language universals can be found. A complementary point of view is to determine if vocalic hesitations can be considered as bearing language-specific information. An additional point of interest concerns the link between vocalic hesitations and the vowels in the phonemic inventory of each language. Finally, the gained insights are of interest to research in acoustic modeling in for automatic speech, speaker and language recognition.

Hesitations have been automatically extracted from large corpora of journalistic broadcast speech and parliamentary debates in three languages (French, American English and European Spanish). Duration, fundamental frequency and formant values were measured and compared. Results confirm that vocalic hesitations share (potentially universal) properties across languages, characterized by longer durations and lower fundamental frequency than are observed for intra-lexical vowels in the three languages investigated here. The results on vocalic timbre show that while the measures on hesitations are close to existing vowels of the language, they do not necessarily coincide with them. The measured average timbre of vocalic hesitations in French is slightly more open than its closest neighbor (/œ/). For American English, the average F1 and F2 formant values position the vocalic hesitation as a mid-open vowel somewhere between /2/ and /æ/. The Spanish vocalic hesitation almost completely overlaps with the mid-closed front vowel /e/.