Always plot your data. We're working with conversational corpora and looking at timing data. Here's a density plot of the timing of turn-taking for three corpora of Japanese and Spanish. At least 3 of the distributions look off (non-normal). But why?

Plotting turn duration against offset provides a clue: in the weird looking ones, there’s a crazy number of turns whose negative offset is equal to their duration — something that can happen if consecutive turns in the data share the exact same end time (very unlikely in actual data).

Plotting the actual timing of the turns as a piano roll shows what’s up: the way turns are segmented and overlap are highly improbable ways — imagine a conversation that goes like this! (in red are data points on the diagonal lines above)

Fortunately some of the corpora we have for these languages don’t show this — so we’re using those. If we hadn’t plotted the data in a few different ways it would have been pretty hard to spot, with consequences down the line. So: always plot your data.

*Originally tweeted by @dingemansemark@scholar.social (@DingemanseMark) on November 6, 2021.*