ABSTRACT

Recent research has suggested that re-setting the standard for each administration of a small sample examination, in addition to the high cost, does not adequately maintain similar performance expectations year after year. Small-sample equating methods have shown promise with samples between 20 and 30. For groups that have fewer than 20 students, options are scarcer. This simulation study examined balanced and unbalanced designs across nine equating models including both classic equating models and small-sample models. The study also accounted for varying sample sizes, differences in form difficulty and candidate population, and the size of the anchor set. This study supports the use of nominal weights approaches in combination with either circle-arc or mean equating. Consistent with other research, this study found that the best ways to improve equating results are increases in sample size and/or the number of anchor items across the old and new forms. However, a testing program’s tolerance for reuse will influence the decision to pool administrations.

摘要

最近的研究表明，除了费用高昂之外，为每次小样本检查的管理重新设定标准并不能充分维持年复一年的类似性能预期。小样本等值方法显示了有希望的样本数量在20到30之间。对于少于20名学生的小组，选择很少。这项仿真研究检查了九种平等模型的平衡和不平衡设计，包括经典平衡模型和小样本模型。该研究还考虑了样本数量的变化，形式难度和候选人群的差异以及锚集的大小。这项研究支持结合圆弧或均值等式使用名义权重方法。与其他研究一致，这项研究发现，改善平等结果的最好方法是增加样本数量和/或增加新旧表单中锚项的数量。但是，测试程序对重用的容忍度将影响合并管理的决定。