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An IRtree Model for Aberrant Response and Missing Data
Fangbin Chen1, Daxun Wang1, Yan Cai1
1School of Psychology, Jiangxi Normal University, Nanchang, China.
This study introduces the IRTree model to accurately analyze various test-taking behaviors like guessing and cheating. The model improves the precision of ability and item parameter estimates in standardized testing.
Area of Science:
- Psychometrics
- Educational Measurement
Background:
- Standardized tests can yield inaccurate results due to non-standard examinee behaviors.
- Behaviors like rapid guessing, cheating, and nonresponse compromise test validity and fairness.
Purpose of the Study:
- To propose an innovative IRTree model for simultaneously analyzing multiple aberrant examinee behaviors.
- To enhance the accuracy of ability and item parameter estimation in standardized assessments.
Main Methods:
- Developed the IRTree model to concurrently model rapid guessing, cheating, and nonresponse behaviors.
- Applied the model to two real datasets and conducted simulation studies for validation.
Main Results:
- The IRTree model provides superior accuracy in estimating person and item parameters compared to existing models.
- The model offers enhanced classification of examinee behaviors at both item and examinee levels.
- Successfully separated and simultaneously modeled guessing and cheating behaviors for the first time.
Conclusions:
- The IRTree model effectively addresses limitations in current testing methodologies by accounting for diverse examinee behaviors.
- The model demonstrates improved precision and validity in psychometric assessments.
- Further research should explore the boundary conditions for the model's application.
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