The external validity of scores based on the two-parameter logistic model: Some comparisons between IRT and CTT
2007
A theoretical advantage of item response theory (IRT) models is that trait
estimates based on these models provide more test information than any
other type of test score. It is still unclear, however, whether using IRT trait
estimates improves external validity results in comparison with the results
that can be obtained by using simple raw scores. This paper discusses some
methodological results based on the 2-parameter logistic model (2PLM) and
is concerned with three issues: first, how validity coefficients based on IRT
trait estimates must be interpreted; second, how inferences about these
coefficients can be made; and third, which differences in external validity
can be expected if the 2PLM is correct for the data and IRT scores are used
in place of raw scores. Four empirical examples in the personality domain
provided further evidence for the results that can be expected in real
research in which the model is, at best, a good approximation to the data. A
general result of these examples was that validity coefficients based on IRT
scores were similar to those based on raw scores
Keywords:
- Correction
- Source
- Cite
- Save
- Machine Reading By IdeaReader
32
References
9
Citations
NaN
KQI