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ERIC Number: EJ829930
Record Type: Journal
Publication Date: 2009
Pages: 16
Abstractor: As Provided
Reference Count: 38
ISSN: ISSN-0146-6216
Item Response Theory with Estimation of the Latent Density Using Davidian Curves
Woods, Carol M.; Lin, Nan
Applied Psychological Measurement, v33 n2 p102-117 2009
Davidian-curve item response theory (DC-IRT) is introduced, evaluated with simulations, and illustrated using data from the Schedule for Nonadaptive and Adaptive Personality Entitlement scale. DC-IRT is a method for fitting unidimensional IRT models with maximum marginal likelihood estimation, in which the latent density is estimated, simultaneously with the item parameters of logistic item response functions, as a Davidian curve. Simulations compare DC-IRT with Ramsay-curve IRT (RC-IRT) and the empirical histogram method (EHM) for a normal, bimodal, or skewed latent distribution. When the latent density was nonnormal, any of the three density estimation methods improved on the normal model. Both DC-IRT and RC-IRT produced more-accurate results than did the EHM. (Contains 3 figures, 3 tables and 3 notes.)
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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