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This content will become publicly available on July 1, 2024

Title: Knowledge Tracing Over Time: A Longitudinal Analysis
The use of Bayesian Knowledge Tracing (BKT) models in predicting student learning and mastery, especially in mathematics, is a well-established and proven approach in learning analytics. In this work, we report on our analysis examining the generalizability of BKT models across academic years attributed to ”detector rot.” We compare the generalizability of Knowledge Training (KT) models by comparing model performance in predicting student knowledge within the academic year and across academic years. Models were trained on data from two popular open-source curricula available through Open Educational Resources. We observed that the models generally were highly performant in predicting student learning within an academic year, whereas certain academic years were more generalizable than other academic years. We posit that the Knowledge Tracing models are relatively stable in terms of performance across academic years yet can still be susceptible to systemic changes and underlying learner behavior. As indicated by the evidence in this paper, we posit that learning platforms leveraging KT models need to be mindful of systemic changes or drastic changes in certain user demographics.  more » « less
Award ID(s):
1917545
NSF-PAR ID:
10443312
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
The Proceedings of the 16th International Conference on Educational Data Mining
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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