Performance of the S-X[superscript 2] Statistic for the Multidimensional Graded Response Model

Autor/inn/en	Su, Shiyang; Wang, Chun; Weiss, David J.
Titel	Performance of the S-X[superscript 2] Statistic for the Multidimensional Graded Response Model
Quelle	In: Educational and Psychological Measurement, 81 (2021) 3, S.491-522 (32 Seiten)Infoseite zur Zeitschrift PDF als Volltext Verfügbarkeit
Zusatzinformation	ORCID (Su, Shiyang)
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	0013-1644
DOI	10.1177/0013164420958060
Schlagwörter	Statistics; Goodness of Fit; Test Items; Models; Sample Size; Test Length; Item Response Theory; Statistical Analysis + Suchen Sie Ihr Suchwort? Statistik; Test content; Testaufgabe; Analogiemodell; Item-Response-Theorie; Statistische Analyse
Abstract	S-X[superscript 2] is a popular item fit index that is available in commercial software packages such as "flex"MIRT. However, no research has systematically examined the performance of S-X[superscript 2] for detecting item misfit within the context of the multidimensional graded response model (MGRM). The primary goal of this study was to evaluate the performance of S-X[superscript 2] under two practical misfit scenarios: first, all items are misfitting due to model misspecification, and second, a small subset of items violate the underlying assumptions of the MGRM. Simulation studies showed that caution should be exercised when reporting item fit results of polytomous items using S-X[superscript 2] within the context of the MGRM, because of its inflated false positive rates (FPRs), especially with a small sample size and a long test. S-X[superscript 2] performed well when detecting overall model misfit as well as item misfit for a small subset of items when the ordinality assumption was violated. However, under a number of conditions of model misspecification or items violating the homogeneous discrimination assumption, even though true positive rates (TPRs) of S-X[superscript 2] were high when a small sample size was coupled with a long test, the inflated FPRs were generally directly related to increasing TPRs. There was also a suggestion that performance of S-X[superscript 2] was affected by the magnitude of misfit within an item. There was no evidence that FPRs for fitting items were exacerbated by the presence of a small percentage of misfitting items among them. (As Provided).
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Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2024/1/01