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MethodStatistics1,836AI & ML1,661Decision Sciences932Research Methods1,354Measurement1,745Causal & Evidence532Research Practice118
5 methods in Psychology · Causal & EvidenceClear
Methods at the intersection of your two filters.
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psychometrics

GRM

The Graded Response Model is an item response theory model developed by Fumiko Samejima in 1969 for ordered polytomous items such as Likert-type scales. It estimates both the discriminating power of each item and a set of threshold parameters marking the boundaries between adjacent response categories, while simultaneo

2 sources1969
psychometrics

Ordinal Content Validity

Ordinal content validity replaces the traditional binary (yes/no) expert relevance judgment with a graded, Likert-type rating scale, allowing richer expert opinion to be captured when evaluating whether scale items adequately represent the intended construct domain.

2 sources2003
psychometrics

Ordinal IRT

Ordinal item response theory (ordinal IRT) comprises a family of probabilistic models — most notably the Graded Response Model and the Partial Credit Model — that relate a respondent's standing on a latent trait to the probability of choosing each ordered response category on a polytomous item. It extends classical IRT

2 sources1969
psychometrics

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

2 sources1990
psychometrics

Polytomous item analysis

Polytomous item analysis examines the psychometric behavior of items that have more than two ordered response categories — such as Likert-type scales or partial-credit tasks. It evaluates each item's difficulty thresholds, discriminating power, and category functioning to determine whether the full response scale is be

2 sources1969