NotesFAQContact Us
Search Tips
Back to results
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ1030024
Record Type: Journal
Publication Date: 2014
Pages: 15
Abstractor: As Provided
ISSN: ISSN-0022-0655
IRT-Estimated Reliability for Tests Containing Mixed Item Formats
Shu, Lianghua; Schwarz, Richard D.
Journal of Educational Measurement, v51 n2 p163-177 Sum 2014
As a global measure of precision, item response theory (IRT) estimated reliability is derived for four coefficients (Cronbach's a, Feldt-Raju, stratified a, and marginal reliability). Models with different underlying assumptions concerning test-part similarity are discussed. A detailed computational example is presented for the targeted coefficients. A comparison of the IRT model-derived coefficients is made and the impact of varying ability distributions is evaluated. The advantages of IRT-derived reliability coefficients for problems such as automated test form assembly and vertical scaling are discussed.
Wiley-Blackwell. 350 Main Street, Malden, MA 02148. Tel: 800-835-6770; Tel: 781-388-8598; Fax: 781-388-8232; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Evaluative
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A