The knowledge tracing (KT) model based on deep learning has been proven to be superior to the traditional knowledge tracing model, eliminating the need for artificial engineering features. However, there are still problems, such as insufficient interpretability of the learning and answering processes. To address these issues, we propose a new approach in knowledge tracing with attention-based embedding and forgetting curve integration, namely KVFKT. Firstly, the embedding representation module is responsible for embedding the questions and computing the attention vector of knowledge concepts (KCs) when students answer questions and when answer time stamps are collected. Secondly, the forgetting quantification module performs the pre-prediction update of the student’s knowledge state matrix. This quantification involves calculating the interval time and associated forgetting rate of relevant KCs, following the forgetting curve. Thirdly, the answer prediction module generates responses based on students’ knowledge status, guess coefficient, and question difficulty. Finally, the knowledge status update module further refines the students’ knowledge status according to their answers to the questions and the characteristics of those questions. In the experiment, four real-world datasets are used to test the model. Experimental results show that KVFKT better traces students’ knowledge state and outperforms state-of-the-art models.

The widespread existence of wrongly labeled instances is a challenge to distantly supervised relation extraction. Most of the previous works are trained in a bag-level setting to alleviate such noise. However, sentence-level training better utilizes the information than bag-level training, as long as combined with effective noise alleviation. In this work, we propose a novel Transitive Instance Weighting mechanism integrated with the self-distilled BERT backbone, utilizing information in the intermediate outputs to generate dynamic instance weights for denoised sentence-level training. By down-weighting wrongly labeled instances and discounting the weights of easy-to-fit ones, our method can effectively tackle wrongly labeled instances and prevent overfitting. Experiments on both held-out and manual datasets indicate that our method achieves state-of-the-art performance and consistent improvements over the baselines.

Distantly supervised relation extraction is widely used in the construction of knowledge bases due to its high efficiency. However, the automatically obtained instances are of low quality with numerous irrelevant words. In addition, the strong assumption of distant supervision leads to the existence of noisy sentences in the sentence bags. In this paper, we propose a novel Multi-Layer Revision Network (MLRN) which alleviates the effects of word-level noise by emphasizing inner-sentence correlations before extracting relevant information within sentences. Then, we devise a balanced and noise-resistant Confidence-based Multi-Instance Learning (CMIL) method to filter out noisy sentences as well as assign proper weights to relevant ones. Extensive experiments on two New York Times (NYT) datasets demonstrate that our approach achieves significant improvements over the baselines.