Positional and planning effects on the durational structure of repetition strings

Gaining time to resolve some difficulty in the production of upcoming speech is the primary function of unplanned repetitions. Understanding their duration structure is thus crucial to modeling their production, which surely differs greatly from fluent phrases. When the duration structure of the entire repetition string of unplanned repetitions is examined, strong global dependencies are found. Repetition strings are words/phrases repeated once or more, together with silent and filled pauses optionally occurring next to them. The main effects are that durations of first and second string items, whether repeated words or pauses, are positively correlated with the duration of the rest of the string; items, whether words or pauses, are shorter as they occur later in the string; and strings that begin with a pause average longer than strings that do not. The study is based on an analysis of 503 disfluent repetitions taken from the ICSI phonetically transcribed sample of the Switchboard conversation corpus, ex...