Accession Number : ADA194212

Title :   A Nonparametric Multidimensional IRT Approach with Applications to Ability Estimation and Test Bias.

Descriptive Note : Technical rept.,

Corporate Author : ILLINOIS UNIV AT URBANA PSYCHOMETRIC GROUP

Personal Author(s) : Stout, William

PDF Url : ADA194212

Report Date : Apr 1988

Pagination or Media Count : 55

Abstract : A determined case is made for the use of a nonparametric multidimensional monotonic IRT modeling framework with local independence replaced by the less restrictive assumption of essential independence. The concept of essential dimensionality is then introduced to count the number of dominant latent dimensions. Consequences of this more general approach include the consistent estimation of ability on a common scale using a natural class of estimators, uniqueness of the latent ability when essential unidimensionality holds, a theoretical treatment of test bias, an IRT based notion of validity, and a reassessment of the importance of the concept of item parameter invariance. Keywords: Local independence; Essential independence; Essential trait; Intrinsic ability scale; Marginal item response function; Latent dimensionality; Multidimensionality; Essential dimensionality; Essential unidimensionality; Item response theory; Latent trait theory; Ability estimation; Consistent estimation; Item parameter invariance; Validity; Linear formula scoring; Nonparametric.

Descriptors :   *NONPARAMETRIC STATISTICS, *STATISTICAL TESTS, BIAS, CONSISTENCY, ESTIMATES, FORMULATIONS, FUNCTIONS, INVARIANCE, PARAMETERS, RESPONSE, SCALE, SCORING, THEORY

Subject Categories : Statistics and Probability

Distribution Statement : APPROVED FOR PUBLIC RELEASE