Linganisha mbinu

	Nadharia ya Majibu ya Kipengee cha Ordinal	Kufanya Kazi Tofauti kwa Vipengele (DIF)
Nyanja	Saikometriki	Saikometriki
Familia	Latent structure	Latent structure
Mwaka wa asili	1969	1970s–1993
Mwanzilishi	Fumiko Samejima (Graded Response Model, 1969); Gerhard Fischer & Georg Rasch lineage for partial credit	William H. Angoff and colleagues (ETS); systematized by Holland & Wainer
Aina	Probabilistic latent trait model for ordered polytomous responses	Item-level bias detection
Chanzo asilia	Samejima, F. (1969). Estimation of latent ability using a response pattern of graded scores. Psychometrika Monograph Supplement, 34(4, Pt. 2), 1–97.	Holland, P. W. & Wainer, H. (Eds.) (1993). Differential Item Functioning. Lawrence Erlbaum Associates. ISBN: 978-0805809589
Majina mbadala	polytomous IRT, ordinal IRT models, graded response models, ordinal latent trait models	DIF, item bias analysis, measurement non-equivalence, item-level measurement bias
Zinazohusiana	6	5
Muhtasari	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 beyond dichotomous items to the Likert-type and rating-scale items that dominate psychometric measurement.	Differential item functioning identifies test or survey items that behave differently for examinees from different groups — such as gender, ethnicity, or language background — after controlling for the underlying ability or trait being measured. DIF analysis is essential for fairness evaluation in educational testing and psychological scale development.