open_dbm/docs/website/versioned_docs/version-2.0/lexical-richness.md

id, title

id	title
lexical-richness	Lexical Richness

There are several terms for this measurement used across literature (sometimes also called diversity in vocabulary, etc.) and certainly more than one way to quantify it. We felt that an appropriate measure of richness of vocabulary would be the Moving Average Type Token Ratio (MATTR), reported in this paper by Convington and McFall¹ . Simply put, it quantifies how many unique words are used in speech, which can be a proxy to some clinical measurements.

Derived Variables

Variable	Description
nlp_mattr_mean	Lexical richness, measured using the moving average type token ratio (MATTR).

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1. Covington, M. A., & McFall, J. D. (2010). Cutting the Gordian knot: The moving-average type–token ratio (MATTR). Journal of quantitative linguistics, 17(2), 94-100. ↩︎