Trajectory-Based Recommender Systems as Control Systems
2026-06-22 • Information Retrieval
Information Retrieval
AI summaryⓘ
The authors look at a special kind of recommendation system called Trajectory-Based Recommender Systems (TBRS), which focus on guiding users toward long-term goals rather than one-time suggestions. They suggest using Control Theory, a way to mathematically manage changing systems, to better understand and build these TBRS. They point out that many existing recommendation systems with long-term goals haven't been grouped together in research before. The authors also explain how Educational Recommender Systems, which aim to help learners achieve long-range objectives, fit well into this TBRS approach.
Recommender SystemsTrajectory-Based Recommender SystemsControl TheoryLong-Term GoalsEducational Recommender SystemsGoal-Driven SystemsMathematical ModelingUser TrajectorySystem Dynamics
Authors
Eriam Schaffter, Ahmed Bounekkar, Elsa Negre
Abstract
Recommender Systems (RS) are a key research domain and play an increasing role in our content-overwhelmed lives. In this paper, we explore Trajectory-Based Recommender Systems (TBRS), a subfield for which many related studies exist, yet still lacking a common framework. We argue that Control Theory provides an appropriate foundation for formalizing and solving TBRS problems. TBRS, sometimes named Long Term goal Recommender Systems, share core principles with classical RS, but at their core lies the concept of a trajectory, a defining element that makes these systems a singular category. To date, most RSs that include a notion of goal or long-term objective, when this goal is explicit, have not been recognized as having specific characteristics that make them worth regrouping under a dedicated field of research. We review related work, observe how they differ from already conceptualized RSs, and sketch the foundations of a possible theoretical framework based on control theory. Finally, we show how Educational Recommender Systems (ERS), intrinsically long-term and goal-driven, can be modeled within the proposed TBRS framework.