认知诊断测验项目开发成本较高,要标定大量项目的属性相当费时费力,专家完成这一任务也比较困难。对于在计算机化自适应诊断测验中的项目属性的标定尚未见到报导。在已有的为诊断测验开发的小型题库基础上,本文在计算机化自适应认知诊断测验过程中,植入原始题,对项目属性标定的问题进行探讨,重点研究原始题属性标定的方法及其影响因素,除了MMLE方法和MLE方法外,还建立了一种新的可用于所有非补偿认知诊断模型的属性标定的方法——交差方法。MonteCarlo模拟结果显示,MMLE方法较MLE方法好;在知识状态估计精度较高时,自适应植入原始题较随机植入原始题有一定的优势;随着知识状态估计精度提高和原始题作答次数增加,交差方法与MLE方法基本相当,只是在发散型和无结构型表现欠佳,但是交差方法不需要预先设定项目参数值。
Cognitive Diagnostic Assessment (CDA) combining psychometrics and cognitive science has received increased attention recently, but it is still in its infancy (Leighton and Gierl, 2007). The CDA based on the incidence Q-matrix (Tatsuoka, 1990) is quite different from the traditional Item Response Theory. The entries in each column of the incidence Q-matrix indicate which skills and knowledge are involved in the solution of each item. So the Q-matrix plays an important role in establishing the relation between the latent knowledge states and the ideal response patterns so as to provide information about students' cognitive strengths and weaknesses. On the other hand, CDA requires the specifications which latent attributes are measured by the test items and how these characteristics are related to one another. Leighton, Gierl and Hunka (2004) indicated the logic of Attribute Hierarchy Method (AHM) as following. Firstly, the hierarchy of attributes must be specified through protocol techniques before test item construction. Secondly, test items are developed by specialists according to the attribute hierarchy and finally, the hierarchy of attributes and item attributes are necessary to be validated. In real situations, whether the items have or have not been identified attributes before its construction, it will cost a lot of money, require more efforts to identify attributes through specialists according the above described procedure and yet can't completely assume the correctness due to the subjectivity. As a result, invalid inferences about the student performance will be made if the attributes of some items are specified incorrectly. Chang (2010) pointed out that the on-line calibration for regular computerized adaptive testing may be one of the most effective processes, Although the great significance of Q-matrix in CDA has been widely recognized, few, if any, on-line item attribute identification has been found in the literature. So this study discussed how to implement the on-line i