SemEval-2025 Task 5: LLMs4Subjects -- LLM-based Automated Subject Tagging for a National Technical Library's Open-Access Catalog
Jennifer D'Souza, Sameer Sadruddin, Holger Israel, Mathias Begoin, Diana Slawig
TL;DR
This paper presents SemEval-2025 Task 5 LLMs4Subjects, a benchmark for automated subject tagging in the German/English TIBKAT catalog using the GND taxonomy. It evaluates a range of LLM-based and retrieval-driven systems on two dataset collections (all-subjects and tib-core), with bilingual processing and a top-k subject recommendation setting. Key findings show multilingual models, synthetic data augmentation, and retrieval-augmented pipelines materially boost performance, while very large LLMs do not always outperform well-engineered, smaller systems. The study also integrates qualitative expert assessments, revealing domain-specific strengths and weaknesses, and sets the stage for energy-efficient LLM research in a follow-up edition. All data, code, and resources are openly available, enabling replication and future extensions of this benchmark and its evaluation framework.
Abstract
We present SemEval-2025 Task 5: LLMs4Subjects, a shared task on automated subject tagging for scientific and technical records in English and German using the GND taxonomy. Participants developed LLM-based systems to recommend top-k subjects, evaluated through quantitative metrics (precision, recall, F1-score) and qualitative assessments by subject specialists. Results highlight the effectiveness of LLM ensembles, synthetic data generation, and multilingual processing, offering insights into applying LLMs for digital library classification.
