Will the Real Discrepant Learning Disabilit Please Stand Up?
- 1 May 2002
- journal article
- research article
- Published by SAGE Publications in Journal of Learning Disabilities
- Vol. 35 (3) , 209-213
- https://doi.org/10.1177/002221940203500303
Abstract
Willson and Reynolds (in this issue) challenged my thesis that the regression-based discrepancy method (RDM) is not a valid tool to detect aptitude-achievement discrepancies. In this response, I show that the statistical and theoretical counterarguments of Willson and Reynolds are based on a misreading of the statistical models presented. Furthermore, I demonstrate that the regression adjustment, which is largest for lower correlations, is the direct source of the lack of validity of the RDM procedure. Nevertheless, RDM can be considered a valid method to measure an achievement component that is unrelated to intelligence.Keywords
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