IQ Variations across Time, Race, and Nationality: An Artifact of Differences in Literacy Skills

  title={IQ Variations across Time, Race, and Nationality: An Artifact of Differences in Literacy Skills},
  author={David F. Marks},
  journal={Psychological Reports},
  pages={643 - 664}
  • D. F. Marks
  • Published 2010
  • Psychology, Medicine
  • Psychological Reports
A body of data on IQ collected over 50 years has revealed that average population IQ varies across time, race, and nationality. An explanation for these differences may be that intelligence test performance requires literacy skills not present in all people to the same extent. In eight analyses, population mean full scale IQ and literacy scores yielded correlations ranging from .79 to .99. In cohort studies, significantly larger improvements in IQ occurred in the lower half of the IQ… Expand

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