NotesFAQContact Us
Search Tips
Peer reviewed Peer reviewed
Direct linkDirect link
ERIC Number: EJ772960
Record Type: Journal
Publication Date: 2007
Pages: 15
Abstractor: Author
Reference Count: 19
ISSN: ISSN-0022-0655
Generating Dichotomous Item Scores with the Four-Parameter Beta Compound Binomial Model
Monahan, Patrick O.; Lee, Won-Chan; Ankenmann, Robert D.
Journal of Educational Measurement, v44 n3 p211-225 Fall 2007
A Monte Carlo simulation technique for generating dichotomous item scores is presented that implements (a) a psychometric model with different explicit assumptions than traditional parametric item response theory (IRT) models, and (b) item characteristic curves without restrictive assumptions concerning mathematical form. The four-parameter beta compound-binomial (4PBCB) strong true score model (with two-term approximation to the compound binomial) is used to estimate and generate the true score distribution. The nonparametric item-true score step functions are estimated by classical item difficulties conditional on proportion-correct total score. The technique performed very well in replicating inter-item correlations, item statistics (point-biserial correlation coefficients and item proportion-correct difficulties), first four moments of total score distribution, and coefficient alpha of three real data sets consisting of educational achievement test scores. The technique replicated real data (including subsamples of differing proficiency) as well as the three-parameter logistic (3PL) IRT model (and much better than the 1PL model) and is therefore a promising alternative simulation technique. This 4PBCB technique may be particularly useful as a more neutral simulation procedure for comparing methods that use different IRT models.
Blackwell Publishing. 350 Main Street, Malden, MA 02148. Tel: 800-835-6770; Tel: 781-388-8599; Fax: 781-388-8232; e-mail:; Web site:
Publication Type: Journal Articles; Reports - Research
Education Level: N/A
Audience: N/A
Language: English
Sponsor: N/A
Authoring Institution: N/A