Use of Item Models in a Large-Scale Admissions Test: A Case Study

Routledge. Available from: Taylor & Francis, Ltd. 325 Chestnut Street Suite 800, Philadelphia, PA 19106. Tel: 800-354-1420; Fax: 215-625-2940; Web site: http://www.tandf.co.uk/journals

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28

College Entrance Examinations; Case Studies; Test Items; Models; Automation; Measurement; Scoring

10.1080/15305050802262019

1530-5058

"Item models" (LaDuca, Staples, Templeton, & Holzman, 1986) are classes from which it is possible to generate items that are equivalent/isomorphic to other items from the same model (e.g., Bejar, 1996, 2002). They have the potential to produce large numbers of high-quality items at reduced cost. This article introduces data from an application of item models for the generation of items for a large-scale assessment and investigates several research questions associated with the data. We begin by reviewing calibration techniques for the analysis of data involving item models; one method assumes that the items are isomorphic, while the other treats items generated from the same item model as distinct but related. A major question for these types of data is whether these items are isomorphic; that is, if they behave the same psychometrically. This article describes a number of rough diagnostic measures and a statistical diagnostic to assess the extent of isomorphicity in the items generated from an item model. Finally, this article discusses the issue of scoring--an area that needs more research--with data involving item models. (Contains 4 tables and 9 figures.)

As Provided

31

2008

EJ805764