Knowledge Tracing (KT) aims to trace changes in students' knowledge states throughout their entire learning process by analyzing their historical learning data and predicting their future learning performance. Existing forgetting curve theory based knowledge tracing models only consider the general forgetting caused by time intervals, ignoring the individualization of students and the causal relationship of the forgetting process. To address these problems, we propose a Concept-driven Personalized Forgetting knowledge tracing model (CPF) which integrates hierarchical relationships between knowledge concepts and incorporates students' personalized cognitive abilities. First, we integrate the students' personalized capabilities into both the learning and forgetting processes to explicitly distinguish students' individual learning gains and forgetting rates according to their cognitive abilities. Second, we take into account the hierarchical relationships between knowledge points and design a precursor-successor knowledge concept matrix to simulate the causal relationship in the forgetting process, while also integrating the potential impact of forgetting prior knowledge points on subsequent ones. The proposed personalized forgetting mechanism can not only be applied to the learning of specifc knowledge concepts but also the life-long learning process. Extensive experimental results on three public datasets show that our CPF outperforms current forgetting curve theory based methods in predicting student performance, demonstrating CPF can better simulate changes in students' knowledge status through the personalized forgetting mechanism.

翻译：知识追踪旨在通过学习者的历史学习数据，追踪其在整个学习过程中的知识状态变化，并预测其未来的学习表现。现有基于遗忘曲线理论的知识追踪模型仅考虑时间间隔引起的普遍遗忘，忽略了学习者的个体差异性以及遗忘过程的因果关系。为解决这些问题，我们提出了一种基于概念驱动的个性化遗忘知识追踪模型（CPF），该模型融合了知识概念之间的层级关系，并纳入了学习者的个性化认知能力。首先，我们将学习者的个性化能力融入学习与遗忘过程，以根据其认知能力清晰区分个体的学习增益和遗忘速率。其次，我们考虑知识点间的层级关系，设计了前驱-后继知识概念矩阵以模拟遗忘过程中的因果关系，同时整合了前驱知识遗忘对后续知识点的潜在影响。所提出的个性化遗忘机制不仅适用于特定知识概念的学习，还可应用于终身学习过程。在三个公开数据集上的大量实验结果表明，我们的CPF模型在预测学习者表现方面优于当前基于遗忘曲线理论的方法，证明了CPF能够通过个性化遗忘机制更准确地模拟学习者知识状态的变化。