Regional Variation in West and East Coast African-American English Prosody and Rap Flows.

Only 16 rappers were analyzed, 8 per coast, all male African-American artists from two metropolitan areas, so the findings may not represent other African-American English speakers, women, rappers from other cities, or less famous artists. Recordings were selected from interviews and commercially successful songs, not randomly sampled speech or rap, and selection depended on available high-quality recordings. The rap pitch result was not significant overall and became significant only in an exploratory analysis that excluded Kendrick Lamar, so the regional pitch difference in rap is not firmly established. The MIDI method required manual recreation of rhythm, which can introduce timing error, although the authors reported excellent inter-coder reliability. The study reports acoustic differences in speech and rap, not patient outcomes, communication disorders, or therapy methods.

The authors reported financial support from the University of Groningen for the research and authorship of the article.

Do not conclude that West Coast rap is melodically distinct from East Coast rap. The rap pitch difference was not significant, and it became significant only after a West Coast rapper was excluded in an exploratory analysis. Do not treat these regional speech and rap differences as evidence of a disorder or as guidance for therapy.