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arXiv · 2601.11427

Isotropy-Optimized Contrastive Learning for Semantic Course Recommendation

Ali Khreis·Anthony Nasr·Yusuf Hilal
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Abstract

This paper presents a semantic course recommendation system for students using a self-supervised contrastive learning approach built upon BERT (Bidirectional Encoder Representations from Transformers). Traditional BERT embeddings suffer from anisotropic representation spaces, where course descriptions exhibit high cosine similarities regardless of semantic relevance. To address this limitation, we propose a contrastive learning framework with data augmentation and isotropy regularization that produces more discriminative embeddings. Our system processes student text queries and recommends Top-N relevant courses from a curated dataset of over 500 engineering courses across multiple faculties. Experimental results demonstrate that our fine-tuned model achieves improved embedding separation and more accurate course recommendations compared to vanilla BERT baselines.

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Ali Khreis, Anthony Nasr, Yusuf Hilal. 2026-01-16. Isotropy-Optimized Contrastive Learning for Semantic Course Recommendation. https://arxiv.org/abs/2601.11427

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