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ERIC Number: EJ956923
Record Type: Journal
Publication Date: 2012-Jan
Pages: 4
Abstractor: As Provided
ISSN: ISSN-0146-6216
PROC NLMIXED: For Estimating Parameters of IRT Models
Nandakumar, Ratna; Hotchkiss, Lawrence
Applied Psychological Measurement, v36 n1 p60-63 Jan 2012
The PROC NLMIXED procedure in Statistical Analysis System can be used to estimate parameters of item response theory (IRT) models. The data for this procedure are set up in a particular format called the "long format." The long format takes a substantial amount of time to execute the program. This article describes a format called the "wide format" to estimate parameters of an IRT model more efficiently. The wide format substantially reduces execution time for models with few parameters. But the time savings decline as the number of parameters increases. (Contains 5 tables.)
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Publication Type: Journal Articles; Reports - Descriptive
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A