📖Summing Up Hours of Any Type of Practice Versus Identifying Optimal Practice Activities

Ericsson, K. Anders
  • Macnamara2016 summed up different types of activities, not only deliberate practice

    • activities included group activities, watching games on television, and even play and competition
  • designed by teacher or coach
  • beginner’s performance is often correlated with general ability tests (like IQ), but expert’s rely on domain-specific skills and models which removes reliance on general abilities (and removes correlation)

Flaws of Macnamara2016 (and Macnamara2014)

  • included studies that analyzed non-expert performance (small percentile of experts present in the study)
  • some studies with real deliberate practice and very high correlation (0.87 / 0.92) were excluded from meta-analysis
  • studies that included multiple activities (both deliberate practice and not) with different correlations from -0.51 to 0.62 were averaged to 0.17 and included in meta analysis
  • includes studies with subjective estimates of performance