Sources of Error in IRT Trait Estimation.

ABSTRACT: In item response theory (IRT), item response probabilities are a function of item characteristics and latent trait scores. Within an IRT framework, trait score misestimation results from (a) random error, (b) the trait score estimation method, (c) errors in item parameter estimation, and (d) model misspecification. This study investigated the relative effects of these error sources on the bias and confidence interval coverage rates for trait scores. Our results showed that overall, bias values were close to 0, and coverage rates were fairly accurate for central trait scores and trait estimation methods that did not use a strong Bayesian prior. However, certain types of model misspecifications were found to produce severely biased trait estimates with poor coverage rates, especially at extr

SUBMITTER: Feuerstahler LM 

PROVIDER: S-EPMC6023095 | biostudies-literature | 2018 Jul

REPOSITORIES: biostudies-literature