认知诊断评估的主要问题是如何准确进行被试分类和项目属性标定。本文使用概率神经网络(PNN)和支持向量机(SVM)进行被试分类和属性标定,重点讨论PNN用于诊断的理论根据。模拟研究表明:PNN方法表现最好,训练速度快且具有很好判准率和标定准确率;PNN与GDD方法在分类上表现相当,在独立结构下PNN更好;线性SVM具有较好判准率和标定准确率。软计算中此类方法可非常方便推广至多级评分测验数据分析。
Soft computing is a term used in computer science to refer to problems whose solution is unpredictable and uncertain. With the development of society, people are not only satisfied with the achievement test that only gives a total score, but also hope to get more information about the examinees' cognitive states from the examinees' item responses, and to make inferences .about students' cognitive strengths and weaknesses to provide remedy. How to collect specification of item attributes and classification of student's states is critical to cognitive diagnosis. Gierl & Cui (2007) applied Multi-Layer perception (MLP) neural network in the classification of cognitive diagnosis. Shu et al. (2013) also used MLP result as the precursor to the attribute profile to increase the accuracy of item parameter estimates. This article not only employs the other artificial neural networks (probabilistic neural networks, PNN), but also employs SVM (linear and non-linear SVM) for the classification of attribute profile and aiding specification of Q-matrix. It mainly discusses the reasonability of PNN for the classification of attribute profile. These methods are applied to the 0, 1 scoring test, and then comparisons of the classification results are made with some of the typical methods of attribute hierarchy model: method A (Leighton, Gierl, Hunka, 2004) and generalized distance discrimination (GDD). Furthermore, the Monte Carlo simulation study is used to examine the performance of these methods. In the simulation study, the pattern match ratio and average attribute match ratio are used as criteria to evaluate the classification accuracy of different approaches. Under four attribute hierarchical structures (linear, convergent, divergent, unstructured) used in the attribute hierarchy method of Leighton et al. (2004) and another structure with independent attributes, five kinds of Q-matrix with 6 attributes were simulated individually. Under each type of Q-matrix, we used four kind