I've recently been working with Naomi Nevler and others from Penn's Frontotemporal Degeneration Center on quantifying the diverse effects in speech and language of various neurodegenerative conditions. As part of an effort to establish baselines, I turned to the English-language part of the "Fisher" datasets of conversational telephone speech (LDC2004S13, LDC2004T19, LDC2005S13, LDC2005T19), where we have basic demographic information for 11,971 speakers, including age and sex. These datasets comprise 11,699 short telephone conversations between strangers on assigned topics, or 23,398 conversational sides, with a total duration of 1,958.5 hours. The calls were recorded in 2003.
For this morning's Breakfast Experiment™, I took a look at age-related changes in pitch range, as quantified by quantiles of fundamental frequency (f0) estimates. We have time-aligned transcripts, so after pitch-tracking everything, I can extract the f0 estimates for each speaker, combine them across calls if the speaker was involved in more than one call, and calculate various simple statistics. Here are the median values for the 90th, 50th, and 10th percentile of f0 estimates by decade of age from 20s to 70s. Values for female speakers are in red, and for male speakers in blue:
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