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ERIC Number: EJ929737
Record Type: Journal
Publication Date: 2011
Pages: 19
Abstractor: As Provided
Reference Count: 33
ISSN: ISSN-0022-0655
Relating Unidimensional IRT Parameters to a Multidimensional Response Space: A Review of Two Alternative Projection IRT Models for Scoring Subscales
Kahraman, Nilufer; Thompson, Tony
Journal of Educational Measurement, v48 n2 p146-164 Sum 2011
A practical concern for many existing tests is that subscore test lengths are too short to provide reliable and meaningful measurement. A possible method of improving the subscale reliability and validity would be to make use of collateral information provided by items from other subscales of the same test. To this end, the purpose of this article is to compare two different formulations of an alternative Item Response Theory (IRT) model developed to parameterize unidimensional projections of multidimensional test items: Analytical and Empirical formulations. Two real data applications are provided to illustrate how the projection IRT model can be used in practice, as well as to further examine how ability estimates from the projection IRT model compare to external examinee measures. The results suggest that collateral information extracted by a projection IRT model can be used to improve reliability and validity of subscale scores, which in turn can be used to provide diagnostic information about strength and weaknesses of examinees helping stakeholders to link instruction or curriculum to assessment results.
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Publication Type: Journal Articles; Reports - Evaluative
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A