Complementing educational recommender systems with open learner models

Educational recommender systems (ERSs) aim to adaptively recommend a broad range of personalised resources and activities to students that will most meet their learning needs. Commonly, ERSs operate as a "black box" and give students no insight into the rationale of their choice. Recent contributions from the learning analytics and educational data mining communities have emphasised the importance of transparent, understandable and open learner models (OLMs) that provide insight and enhance learners' understanding of interactions with learning environments. In this paper, we aim to investigate the impact of complementing ERSs with transparent and understandable OLMs that provide justification for their recommendations. We conduct a randomised control trial experiment using an ERS with two interfaces ("Non-Complemented Interface" and "Complemented Interface") to determine the effect of our approach on student engagement and their perception of the effectiveness of the ERS. Overall, our results suggest that complementing an ERS with an OLM can have a positive effect on student engagement and their perception about the effectiveness of the system despite potentially making the system harder to navigate. In some cases, complementing an ERS with an OLM has the negative consequence of decreasing engagement, understandability and sense of fairness.