Processing the prosody of oral presentations

Standard advice to people preparing to speak in public is to use a “lively” voice. A lively voice is described as one that varies in intonation, rhythm and loudness: qualities that can be analyzed using speech analysis software. This paper reports on a study analyzing pitch variation as a measure of speaker liveliness. A potential application of this approach for analysis would be for rehearsing or assessing the prosody of oral presentations. While public speaking can be intimidating even to native speakers, second language users are especially challenged, particularly when it comes to using their voices in a prosodically engaging manner. The material is a database of audio recordings of twenty 10-minute student oral presentations, where all speakers were college-age Swedes studying Technical English. The speech has been processed using the analysis software WaveSurfer for pitch extraction. Speaker liveliness has been measured as the standard deviation from the mean fundamental frequency over 10-second periods of speech. The standard deviations have been normalized (by division with the mean frequency) to obtain a value termed the pitch dynamism quotient (PDQ). Mean values (for ten minutes of speech) of PDQ per speaker range from a low of 0.11 to a high of 0.235. Individual values for 10-second segments range from lows of 0.06 to highs of 0.36.