In this study we compare the ESTER corpus of journalistic speech  and the NCCF corpus of spontaneous speech  in terms of duration, F0 and spectral reduction in productions automatically detected as speech units between pauses. Continuation F0 rises are overall absent in spontaneous speech and speech units reveal a declination slope with less amplitude than in journalistic speech. For both corpora, lengthening starts around 60% of the sequence duration, but significantly less in spontaneous speech. Lengthening in the initial part of the sequence is observed in journalistic speech only. As expected we measure a faster speech rate in spontaneous speech with shorter vowel durations implying — partly only — a more important vowel reduction.
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Bibliographic reference. Gendrot, Cédric / Adda-Decker, Martine / Wu, Yaru (2015): "Comparing journalistic and spontaneous speech: prosodic and spectral analysis", In INTERSPEECH-2015, 958-962.