Journal article
Investigating the Impact of Item Parameter Drift for Item Response Theory Models with Mixture Distributions
Frontiers in psychology, Vol.7, pp.255-255
02/24/2016
DOI: 10.3389/fpsyg.2016.00255
PMCID: PMC4764735
PMID: 26941699
Abstract
This study investigates the impact of item parameter drift (IPD) on parameter and ability estimation when the underlying measurement model fits a mixture distribution, thereby violating the item invariance property of unidimensional item response theory (IRT) models. An empirical study was conducted to demonstrate the occurrence of both IPD and an underlying mixture distribution using real-world data. Twenty-one trended anchor items from the 1999, 2003, and 2007 administrations of Trends in International Mathematics and Science Study (TIMSS) were analyzed using unidimensional and mixture IRT models. TIMSS treats trended anchor items as invariant over testing administrations and uses pre-calibrated item parameters based on unidimensional IRT. However, empirical results showed evidence of two latent subgroups with IPD. Results also showed changes in the distribution of examinee ability between latent classes over the three administrations. A simulation study was conducted to examine the impact of IPD on the estimation of ability and item parameters, when data have underlying mixture distributions. Simulations used data generated from a mixture IRT model and estimated using unidimensional IRT. Results showed that data reflecting IPD using mixture IRT model led to IPD in the unidimensional IRT model. Changes in the distribution of examinee ability also affected item parameters. Moreover, drift with respect to item discrimination and distribution of examinee ability affected estimates of examinee ability. These findings demonstrate the need to caution and evaluate IPD using a mixture IRT framework to understand its effects on item parameters and examinee ability.
Details
- Title: Subtitle
- Investigating the Impact of Item Parameter Drift for Item Response Theory Models with Mixture Distributions
- Creators
- Yoon Soo Park - University of Illinois at ChicagoYoung-Sun Lee - Columbia UniversityKuan Xing - University of Illinois at Chicago
- Resource Type
- Journal article
- Publication Details
- Frontiers in psychology, Vol.7, pp.255-255
- Publisher
- Frontiers Media S.A
- DOI
- 10.3389/fpsyg.2016.00255
- PMID
- 26941699
- PMCID
- PMC4764735
- ISSN
- 1664-1078
- eISSN
- 1664-1078
- Language
- English
- Date published
- 02/24/2016
- Academic Unit
- Family and Community Medicine; Office of Consultation and Research in Medical Education
- Record Identifier
- 9984658250102771
Metrics
2 Record Views