Evaluation of Abilities by Grouping for Small IRT Testing Systems
Evaluation of Abilities by Grouping for Small IRT Testing Systems
复制标题
小型IRT测试系统分组能力评价
DOI:
10.1109/iiai-aai.2016.50
复制
发表时间:
2016
期刊:
影响因子:
--
通讯作者:
H. Hirose
中科院分区:
文献类型:
--
作者:
Yoshiko Tokusada;H. Hirose
In applying the adaptive testing equipped with the item response theory to actual cases, it is crucial to know the appropriate number of question items suffice for the specified accuracy. In almost all the systems we have developed so far, we adopt small number of items in a sequence of questions for adaptive testing because too many questions will bore examinees or force to give up completing the tests although estimation accuracy can be obtained. By experience, we set the number of questions to be five. However, too small number of questions will cause less accurate estimates for examinees' abilities. In this paper, we show how the number of questions influences the accuracy of the estimates. For the sake of stable estimation, we made use of Bayes method, which may make shrinkage estimation. In order to make sense to use the estimates, we propose grouping, or classifying to examinees' abilities. The optimal number of groups will be shown as a result. By using simulation studies, we have found that five question items are insufficient to estimate the examinee's true ability. At least ten items are required even if the testing is adaptive.