基于试题-知识点异构图和多特征融合的知识追踪模型  

Knowledge Tracing Model Based on Exercise-Knowledge Point Heterogeneous Graph and Multi-feature Fusion

作　　者：解培中[1] 李冠进 李汀[1] XIE Peizhong;LI Guanjin;LI Ting(School of Communication and Information Engineering,Nanjing University of Posts and Telecommunications,Nanjing 210003,China)

机构地区：[1]南京邮电大学通信与信息工程学院,南京210003

出　　处：《计算机科学》2025年第3期197-205,共9页Computer Science

基　　金：国家自然科学基金(62277032)。

摘　　要：知识追踪要求基于学习者的历史作答情况来预测未来的答题表现,并评估知识状态的变化。探索学习者知识状态的变化有助于实现个性化服务,如课程推荐和试题推荐。然而,现有的大多数知识追踪模型在建模时考虑的特征不够全面,不能综合衡量学习者知识状态的变化。针对这一问题,提出一种新的知识追踪模型——基于试题-知识点异构图和多特征融合的知识追踪模型(EKMFKT)。具体而言,从学习者的学习过程出发,研究了两种行为特征(尝试次数和提示次数)以及两种时间特征(响应时间和间隔时间)对知识状态的影响。然后,设计了学习门和遗忘门,以模拟知识的获取和遗忘,全面更新知识状态的变化。另外,对于模型的输入,设计了基于试题-知识点异构图的图嵌入方法来预训练试题表示,使得模型的输入保持试题和知识点的关联。在两个公开数据集上的实验结果表明,EKMFKT在预测性能上优于现有模型。通过引入多个特征并确保试题与知识点的关联,EKMFKT使知识状态的变化更合理,增强了模型的可解释性。Knowledge tracing(KT)aims to predict a learner’s future performance based on their historical responses and assess changes in their knowledge state.Exploring these changes facilitates personalized services,such as course and exercise recommendations.However,most existing knowledge tracing models do not consider comprehensive features,leading to incomplete assessments of a learner’s knowledge state changes.To address this issue,a new knowledge tracing model-knowledge tracing model based on exercise-knowledge point heterogeneous graph and multi-feature fusion(EKMFKT)is propose.Specifically,we study two behavioral features(attempt and hint)and two temporal features(response time and interval time)and their impact on the knowledge state.To simulate knowledge acquisition and forgetting,we design learning and forgetting gates,which comprehensively update the knowledge state.For model inputs,a graph embedding method based on the question-knowledge point heteroge-neous graph is designed to pre-train question representations,preserving the associations between questions and knowledge points.Experimental results on two public datasets demonstrate that EKMFKT outperforms existing models in predictive performance.By incorporating multiple features and ensuring the connection between question and knowledge point,EKMFKT provides a more reasonable representation of knowledge state changes,enhancing the interpretability of the model.

关 键 词：知识追踪 异构图 学习行为 时间特征 遗忘行为 

分 类 号：G40-057[文化科学—教育学原理]