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Over the past decade, I've noticed that Barack Obama's speaking style often involves short, definite-sounding phrases with steeply falling pitch. For an example, take this clip from his 2009 inaugural address:

I tried to quantify — or at least visualize — some of the temporal aspects of this pattern in "Political sound and silence", 2/8/2016, comparing Obama with G.W. Bush in terms of the distribution of speech segment and silence segment durations.

We can visualize (some aspects of) the associated pitch patterns by looking at dipole difference statistics of f0 estimates, as discussed e.g. in "More on pitch and time intervals in speech", 10/15/2016; "Carl Kasell: diabolus in musica?", 11/5/2016; "Some visualizations of prosody", 10/23/2016. This analysis yields a two-dimensional density plot, where one axis represents time differences and the other axis represents f0 differences. And a syllable-scale plot of f0 dipole difference statistics, from the whole of Obama's 2009 inaugural, does support the intuition about the preponderance of rapid local f0 falls:

But it's natural to ask whether other speakers' oratory in similar circumstances would seem different in this representation.

Donald Trump is a natural point of comparison, since as I've observed from time to time, he's given to long stretches of relatively level f0. See e.g. "Trump's prosody", 8/8/2016, and "Trumpchant in B flat", 10/2/2016. Or listen to these passages from his recent inaugural address:

And the syllable-scale f0 dipole differene plot for the entire 2017 inaugural contrasts with Obama's plot, and supports the intuition of sustains rather than falls:

We can see this in f0 tracks for individual phrases, e.g.

But illustrative examples can be misleading, and so it's nice to see that impressions can be confirmed by objective methods.

As a teaser for further explorations, here's a comparison of syllable-scale f0 dipole density plots for 4-5 minutes of text reading by a female speaker from Belfast:

…compared to the same thing for a female speaker from Cambridge (UK):

The data is from the IViE corpus, and illustrates the theme developed in Eric Jarman and Alan Cruttenden, "Belfast intonation and the myth of the fall", Journal of the International Phonetic Association 1976.

February 2, 2017 @ 8:52 am · Filed by Mark Liberman under Prosody, Rhetoric

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