Outliers: The Story of Success · chapter 2 · id outliers-c2-06-macnamara-hambrick--oswald-201

“Macnamara, Hambrick & Oswald (2014) conducted a meta-analysis of 88 studies (N>11,000) and found deliberate practice explained only 12% of variance in performance overall -- 26% in games, 21% in music, 18% in sports, and just 1% in professions.”

holdsconfidence: high⚠ extracted by pipeline, re-audit pending

Receipts

Macnamara, Hambrick & Oswald (2014), Psychological Sciencesource alive

Deliberate practice explained 26% of the variance in performance for games, 21% for music, 18% for sports, 4% for education, and less than 1% for professions. The overall correlation was 0.35.

Macnamara & Maitra (2019), Royal Society Open Sciencepaywalled — manual check queued

Revisiting Ericsson, Krampe & Tesch-Romer (1993): the role of deliberate practice in expert performance is more limited than originally claimed.

This claim is a stable, citable object. If you can falsify a verdict, tell us — corrections are loud here.