Measure of Textual Lexical Diversity (MTLD)
Mean MTLD per year, computed after McCarthy & Jarvis (2010). Only songs with at least 100 tokens are included. Select an archive below to narrow the view. For window-based alternatives, see Type-Token Ratio (STTR, MATTR) →
Linguistic Insights
MTLD flips the rap picture
Where window-based ratios put rap at the bottom, MTLD places the HipHop Songs archive comparatively high — above Chart Songs and GDR Songs. MTLD measures how long a running text sustains a diversity threshold, so it is less dominated by repeated hooks than a fixed-window ratio (see Type-Token Ratio →). The reversal suggests rap genuinely varies its vocabulary across a song even while leaning on formulaic refrains: the two measures capture different things, not contradictory facts.
Read small archives and sparse years cautiously
Per-song MTLD ranges from under 10 to over 1000, so yearly means in small archives can swing on a few outlier songs, and the y-axis rescales to whatever is in view. Sparse years appear as isolated dots rather than joined to the line. For an artist archive, a single productive year — a new album with unusually varied or unusually formulaic language — can move the archive mean substantially.
Mean MTLD per year · songs with ≥ 100 tokens · factor threshold 0.720 · dots = fewer than 5 songs in that year
These analyses are based on corpus data as of July 29, 2026.