Methoden vergleichen

	Ordinales Rasch-Modell (Rating Scale und Partial Credit Model)	Ordinal Item Analysis
Fachgebiet	Psychometrie	Psychometrie
Familie	Latent structure	Latent structure
Entstehungsjahr	1978–1982	1950s–1980s
Urheber	David Andrich (RSM, 1978); Geoff Masters (PCM, 1982)	Classical test theory tradition (Guilford, Nunnally, and others)
Typ	Item response model for ordered categories	Item-level diagnostic
Wegweisende Quelle	Andrich, D. (1978). A rating formulation for ordered response categories. Psychometrika, 43(4), 561–573.	Nunnally, J. C. & Bernstein, I. H. (1994). Psychometric Theory (3rd ed.). McGraw-Hill. ISBN: 978-0070474659
Aliasnamen	Rating Scale Model, Partial Credit Model, RSM, PCM	item analysis for ordinal data, polytomous item analysis, Likert item analysis, OIA
Verwandt	6	6
Zusammenfassung	The ordinal Rasch model extends the dichotomous Rasch framework to items with ordered response categories such as Likert-type scales. It places both persons and items on a shared interval-level metric, enabling principled measurement from ordinal data while checking whether items function consistently across all response thresholds.	Ordinal item analysis evaluates each individual item in a rating-scale or Likert-type instrument using descriptive and correlational statistics suited to ordered categorical response formats. It guides item selection and refinement by flagging items with problematic difficulty, poor discrimination, or low corrected item-total correlations before reliability and validity studies proceed.