提出了一种基于自注意力融合的多图知识追踪方法(multi-graph knowledge tracing method based on self-attention,SA-MGKT),旨在通过学生的历史答题数据,对其知识的掌握程度进行模型化,并评估其未来学习的表现.首先,该方法构建了学生...提出了一种基于自注意力融合的多图知识追踪方法(multi-graph knowledge tracing method based on self-attention,SA-MGKT),旨在通过学生的历史答题数据,对其知识的掌握程度进行模型化,并评估其未来学习的表现.首先,该方法构建了学生–习题异质图来表示学生–习题的高阶关系,通过图对比学习技术捕获学生的答题偏好,并采用3层LightGCN进行图表征学习.然后,引入概念关联超图和有向转换图的信息,通过超图卷积网络和有向图卷积网络进行节点嵌入.最后,通过引入自注意力机制,成功融合了习题序列的内部信息以及多图表征学习所蕴含的潜在信息,从而显著提升了知识追踪模型的准确性.实验数据在3个标准数据集上均展现出令人鼓舞的结果,模型的分类性能得到了大幅提升,具体表现为相对于基线模型,在评估指标上分别提高了3.51%、17.91%和1.47%.这些结果充分验证了融合多图信息和自注意力机制对于增强知识追踪模型性能的有效性.展开更多
With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery ...With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery of knowledge based on their historical exercise sequences. Nowadays, many related works have emerged in this field, such as Bayesian knowledge tracing and deep knowledge tracing methods. Despite the progress that has been made in KT, existing techniques still have the following limitations: 1) Previous studies address KT by only exploring the observational sparsity data distribution, and the counterfactual data distribution has been largely ignored. 2) Current works designed for KT only consider either the entity relationships between questions and concepts, or the relations between two concepts, and none of them investigates the relations among students, questions, and concepts, simultaneously, leading to inaccurate student modeling. To address the above limitations,we propose a graph counterfactual augmentation method for knowledge tracing. Concretely, to consider the multiple relationships among different entities, we first uniform students, questions, and concepts in graphs, and then leverage a heterogeneous graph convolutional network to conduct representation learning.To model the counterfactual world, we conduct counterfactual transformations on students’ learning graphs by changing the corresponding treatments and then exploit the counterfactual outcomes in a contrastive learning framework. We conduct extensive experiments on three real-world datasets, and the experimental results demonstrate the superiority of our proposed Graph CA method compared with several state-of-the-art baselines.展开更多
Knowledge tracing is the key component in online individualized learning,which is capable of assessing the users'mastery of skills and predicting the probability that the users can solve specific problems.Availabl...Knowledge tracing is the key component in online individualized learning,which is capable of assessing the users'mastery of skills and predicting the probability that the users can solve specific problems.Available knowledge tracing models have the problem that the assessments are not directly used in the predictions.To make full use of the assessments during predictions,a novel model,named deep knowledge tracing embedding neural network(DKTENN),is proposed in this work.DKTENN is a synthesis of deep knowledge tracing(DKT)and knowledge graph embedding(KGE).DKT utilizes sophisticated long short-term memory(LSTM)to assess the users and track the mastery of skills according to the users'interaction sequences with skill-level tags,and KGE is applied to predict the probability on the basis of both the embedded problems and DKT's assessments.DKTENN outperforms performance factors analysis and the other knowledge tracing models based on deep learning in the experiments.展开更多
Programming ability has become one of the most practical basic skills,and it is also the foundation of software development.However,in the daily training experiment,it is difficult for students to find suitable exerci...Programming ability has become one of the most practical basic skills,and it is also the foundation of software development.However,in the daily training experiment,it is difficult for students to find suitable exercises from a large number of topics provided by numerous online judge(OJ)systems.Recommending high passing rate topics with an effective prediction algorithm can effectively solve the problem.Directly applying some common prediction algorithms based on knowledge tracing could bring some problems,such as the lack of the relationship among programming exercises and dimension disaster of input data.In this paper,those problems were analyzed,and a new prediction algorithm was proposed.Additional information,which represented the relationship between exercises,was added in the input data.And the input vector was also compressed to solve the problem of dimension disaster.The experimental results show that deep knowledge tracing(DKT)with side information and compression(SC)model has an area under the curve(AUC)of 0.7761,which is better than other models based on knowledge tracing and runs faster.展开更多
现有知识追踪模型大多以概念为中心评估学生的未来表现,忽略了包含相同概念的练习之间的差异,从而影响模型的预测准确性。此外,在构建学生知识状态过程中,现有模型未能充分利用学生在答题过程中的学习遗忘特征,导致对学生知识状态的刻...现有知识追踪模型大多以概念为中心评估学生的未来表现,忽略了包含相同概念的练习之间的差异,从而影响模型的预测准确性。此外,在构建学生知识状态过程中,现有模型未能充分利用学生在答题过程中的学习遗忘特征,导致对学生知识状态的刻画不够精确。针对以上问题,提出了一种练习嵌入和学习遗忘特征增强的知识追踪模型(exercise embeddings and learning-forgetting features boosted knowledge tracing, ELFBKT)。该模型利用练习概念二部图中的显性关系,深入计算二部图中的隐性关系,构建了一个练习概念异构关系图。为充分利用异构图中的丰富关系信息,ELFBKT模型引入了关系图卷积网络。通过该网络的处理,模型能够增强练习嵌入的质量,并以练习为中心更准确地预测学生的未来表现。此外,ELFBKT充分利用多种学习遗忘特征,构建了两个门控机制,分别针对学生的学习行为和遗忘行为进行建模,更精确地刻画学生的知识状态。在两个真实世界数据集上进行实验,结果表明ELFBKT在知识追踪任务上的性能优于其他模型。展开更多
知识追踪任务旨在根据学生历史学习行为实时追踪学生知识水平变化,并且预测学生在未来学习表现.在学生学习过程中,学习行为与遗忘行为相互交织,学生的遗忘行为对知识追踪影响很大.为了准确建模知识追踪中学习与遗忘行为,提出一种兼顾学...知识追踪任务旨在根据学生历史学习行为实时追踪学生知识水平变化,并且预测学生在未来学习表现.在学生学习过程中,学习行为与遗忘行为相互交织,学生的遗忘行为对知识追踪影响很大.为了准确建模知识追踪中学习与遗忘行为,提出一种兼顾学习与遗忘行为的深度知识追踪模型LFKT(learning and forgetting behavior modeling for knowledge tracing).LFKT模型综合考虑了4个影响知识遗忘因素,包括学生重复学习知识点的间隔时间、重复学习知识点的次数、顺序学习间隔时间以及学生对于知识点的掌握程度.结合遗忘因素,LFKT采用深度神经网络,利用学生答题结果作为知识追踪过程中知识掌握程度的间接反馈,建模融合学习与遗忘行为的知识追踪模型.通过在真实在线教育数据集上的实验,与当前知识追踪模型相比,LFKT可以更好地追踪学生知识掌握状态,并具有较好的预测性能.展开更多
文摘提出了一种基于自注意力融合的多图知识追踪方法(multi-graph knowledge tracing method based on self-attention,SA-MGKT),旨在通过学生的历史答题数据,对其知识的掌握程度进行模型化,并评估其未来学习的表现.首先,该方法构建了学生–习题异质图来表示学生–习题的高阶关系,通过图对比学习技术捕获学生的答题偏好,并采用3层LightGCN进行图表征学习.然后,引入概念关联超图和有向转换图的信息,通过超图卷积网络和有向图卷积网络进行节点嵌入.最后,通过引入自注意力机制,成功融合了习题序列的内部信息以及多图表征学习所蕴含的潜在信息,从而显著提升了知识追踪模型的准确性.实验数据在3个标准数据集上均展现出令人鼓舞的结果,模型的分类性能得到了大幅提升,具体表现为相对于基线模型,在评估指标上分别提高了3.51%、17.91%和1.47%.这些结果充分验证了融合多图信息和自注意力机制对于增强知识追踪模型性能的有效性.
基金supported by the Natural Science Foundation of China (62372277)the Natural Science Foundation of Shandong Province (ZR2022MF257, ZR2022MF295)Humanities and Social Sciences Fund of the Ministry of Education (21YJC630157)。
文摘With the popularity of online learning in educational settings, knowledge tracing(KT) plays an increasingly significant role. The task of KT is to help students learn more effectively by predicting their next mastery of knowledge based on their historical exercise sequences. Nowadays, many related works have emerged in this field, such as Bayesian knowledge tracing and deep knowledge tracing methods. Despite the progress that has been made in KT, existing techniques still have the following limitations: 1) Previous studies address KT by only exploring the observational sparsity data distribution, and the counterfactual data distribution has been largely ignored. 2) Current works designed for KT only consider either the entity relationships between questions and concepts, or the relations between two concepts, and none of them investigates the relations among students, questions, and concepts, simultaneously, leading to inaccurate student modeling. To address the above limitations,we propose a graph counterfactual augmentation method for knowledge tracing. Concretely, to consider the multiple relationships among different entities, we first uniform students, questions, and concepts in graphs, and then leverage a heterogeneous graph convolutional network to conduct representation learning.To model the counterfactual world, we conduct counterfactual transformations on students’ learning graphs by changing the corresponding treatments and then exploit the counterfactual outcomes in a contrastive learning framework. We conduct extensive experiments on three real-world datasets, and the experimental results demonstrate the superiority of our proposed Graph CA method compared with several state-of-the-art baselines.
文摘Knowledge tracing is the key component in online individualized learning,which is capable of assessing the users'mastery of skills and predicting the probability that the users can solve specific problems.Available knowledge tracing models have the problem that the assessments are not directly used in the predictions.To make full use of the assessments during predictions,a novel model,named deep knowledge tracing embedding neural network(DKTENN),is proposed in this work.DKTENN is a synthesis of deep knowledge tracing(DKT)and knowledge graph embedding(KGE).DKT utilizes sophisticated long short-term memory(LSTM)to assess the users and track the mastery of skills according to the users'interaction sequences with skill-level tags,and KGE is applied to predict the probability on the basis of both the embedded problems and DKT's assessments.DKTENN outperforms performance factors analysis and the other knowledge tracing models based on deep learning in the experiments.
文摘Programming ability has become one of the most practical basic skills,and it is also the foundation of software development.However,in the daily training experiment,it is difficult for students to find suitable exercises from a large number of topics provided by numerous online judge(OJ)systems.Recommending high passing rate topics with an effective prediction algorithm can effectively solve the problem.Directly applying some common prediction algorithms based on knowledge tracing could bring some problems,such as the lack of the relationship among programming exercises and dimension disaster of input data.In this paper,those problems were analyzed,and a new prediction algorithm was proposed.Additional information,which represented the relationship between exercises,was added in the input data.And the input vector was also compressed to solve the problem of dimension disaster.The experimental results show that deep knowledge tracing(DKT)with side information and compression(SC)model has an area under the curve(AUC)of 0.7761,which is better than other models based on knowledge tracing and runs faster.
文摘现有知识追踪模型大多以概念为中心评估学生的未来表现,忽略了包含相同概念的练习之间的差异,从而影响模型的预测准确性。此外,在构建学生知识状态过程中,现有模型未能充分利用学生在答题过程中的学习遗忘特征,导致对学生知识状态的刻画不够精确。针对以上问题,提出了一种练习嵌入和学习遗忘特征增强的知识追踪模型(exercise embeddings and learning-forgetting features boosted knowledge tracing, ELFBKT)。该模型利用练习概念二部图中的显性关系,深入计算二部图中的隐性关系,构建了一个练习概念异构关系图。为充分利用异构图中的丰富关系信息,ELFBKT模型引入了关系图卷积网络。通过该网络的处理,模型能够增强练习嵌入的质量,并以练习为中心更准确地预测学生的未来表现。此外,ELFBKT充分利用多种学习遗忘特征,构建了两个门控机制,分别针对学生的学习行为和遗忘行为进行建模,更精确地刻画学生的知识状态。在两个真实世界数据集上进行实验,结果表明ELFBKT在知识追踪任务上的性能优于其他模型。
文摘知识追踪任务旨在根据学生历史学习行为实时追踪学生知识水平变化,并且预测学生在未来学习表现.在学生学习过程中,学习行为与遗忘行为相互交织,学生的遗忘行为对知识追踪影响很大.为了准确建模知识追踪中学习与遗忘行为,提出一种兼顾学习与遗忘行为的深度知识追踪模型LFKT(learning and forgetting behavior modeling for knowledge tracing).LFKT模型综合考虑了4个影响知识遗忘因素,包括学生重复学习知识点的间隔时间、重复学习知识点的次数、顺序学习间隔时间以及学生对于知识点的掌握程度.结合遗忘因素,LFKT采用深度神经网络,利用学生答题结果作为知识追踪过程中知识掌握程度的间接反馈,建模融合学习与遗忘行为的知识追踪模型.通过在真实在线教育数据集上的实验,与当前知识追踪模型相比,LFKT可以更好地追踪学生知识掌握状态,并具有较好的预测性能.