Measuring Word Meaning Change Across Time and Speaker Age - Speaker: Gaurav Kamath
When a language evolves over time, does it change only because newer, younger speakers of the language replace older speakers who conserve older forms of it? Or do those older speakers actually participate in ongoing linguistic changes? In this talk, I present work recently published in PNAS, which asks this question in the context of word meaning change. We analyze meaning change in over 100 words across more than 7.9 million U.S. congressional speeches, to observe whether, when a word sense rises or falls in prominence, adult speakers from different generations uniformly adopt it, or those from older generations conserve their prior usage. We use masked language models to identify different senses of each word, and then model the prevalence of each of these word senses as a function of time and speaker age. We find that most words show only a small effect of speaker age; across almost 140 years of Congress, older speakers typically take longer than younger speakers to follow changes in word usage, but nevertheless do so within a few years. Our findings suggest that despite minor age-based differences, word meaning change among adults is broadly an age-agnostic process, and that older adult speakers are able readily able to adopt new word usage patterns.