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Polytomous DIF/Evidence
Method evidence record

Polytomous DIF

Polytomous differential item functioning detects whether a test or survey item with more than two ordered response categories (e.g., Likert-type scales, partial-credit items) functions differently across groups such as gender, ethnicity, or language background, after controlling for the latent trait being measured. It extends classical binary DIF methods to ordinal response formats.

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Source record

Citations copied verbatim from the method’s source record. No claim-level verification is inferred from them.

Polytomous Differential Item Functioning
Taxonomic method record · latent-structure / psychometrics
  • Zumbo, B. D. (1999). A handbook on the theory and methods of differential item functioning (DIF): Logistic regression modeling as a unitary framework for binary and Likert-type (ordinal) item scores. Directorate of Human Resources Research and Evaluation, Department of National Defense. · URL
  • Osterlind, S. J. & Everson, H. T. (2009). Differential Item Functioning (2nd ed.). SAGE Publications. · ISBN 978-1412954945
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Related methods

Generated from the method graph and shown as machine-suggested relations — no evidence claim is inferred.

Taxonomic bucketConfirmatory factor analysismachine-suggested · Relational suggestion, not evidence.Same method familyGRMmachine-suggested · Relational suggestion, not evidence.Taxonomic bucketItem Response Theorymachine-suggested · Relational suggestion, not evidence.Same method familyMeasurement Invariancemachine-suggested · Relational suggestion, not evidence.

Evidence status

Sources recorded, not reviewed

Bibliographic sources are present. Claim-level evidence review has not been performed.

Sources

2 recorded citations, copied from the method source record.

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