Finch W Holmes, Hernandez Finch Maria E
Department of Educational Psychology, Ball State University, Muncie, IN 47304, USA,
J Appl Meas. 2014;15(2):133-51.
The assessment of differential item functioning (DIF) remains an area of active research in psychometrics and educational measurement. In recent years, methodological innovations involving mixture Rasch models have provided researchers with an additional set of tools for more deeply understanding the root causes of DIF, while at the same time increased interest in the role of disabilities and accommodations has also made itself felt in the measurement community. The current study furthered work in both areas by using the newly described multilevel mixture Rasch model to investigate the presence of DIF associated with disability and accommodation status at both examinee and school levels for a 3rd grade language assessment. Results of the study found that indeed DIF was present at both levels of analysis, and that it was associated with the presence of disabilities and the receipt of accommodations. Implications of these results for both practitioners and researchers are discussed.
差异项目功能（DIF）评估仍然是心理测量学和教育测量领域的一个活跃研究领域。近年来，涉及混合Rasch模型的方法创新为研究人员提供了一套额外的工具，以便更深入地理解DIF的根本原因，与此同时，测量界对残疾和便利条件作用的兴趣增加也有所体现。本研究通过使用新描述的多层次混合Rasch模型，进一步推进了这两个领域的工作，以调查三年级语言评估中考生和学校层面与残疾和便利条件状态相关的DIF的存在情况。研究结果发现，在两个分析层面确实都存在DIF，并且它与残疾的存在和便利条件的获得有关。讨论了这些结果对从业者和研究人员的影响。
