Cite or Decline: A Strict Course-Grounded Chatbot for STEM Lecture Videos

S M Masrur Ahmed, Jaspal Subhlok


Abstract
Recorded lecture videos, often enhanced with search and summarization features, are a standard study resource. However, students cannot easily ask course specific questions or verify answers against an instructor’s lecture. We report a semester-long deployment of VideoPoints platform with a retrieval-augmented chatbot that answers from course lecture materials and returns timestamped citations. The chatbot retrieves only from the active course, uses chapter summaries to guide transcript ranking, and returns clickable timestamped citations. Students used it for quick lookups and exam review. Across 833 messages, 70.5% included citations, none crossed a course boundary, and when no lecture evidence matched, the chatbot usually declined rather than answering. Among the users, citations were the most consistently useful feature, while practice-question generation was the strongest unmet request. We also evaluated the design on the real-world test split of EduVidQA, a public multimodal benchmark for lecture-video question answering. Our design improved correct-lecture retrieval by 6.3 percentage points over dense-only retrieval. Together, the results show that effective deployment depends on course isolation, supported citations, and alignment with students’ study practices.
Anthology ID:
2026.emnlp-industry.250
Volume:
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing: Industry Track
Month:
October
Year:
2026
Address:
Budapest, Hungary
Editors:
Pepa Atanasova, Gholamreza Haffari, Minghan Wang
Venue:
EMNLP
SIG:
SIGDAT
Publisher:
Association for Computational Linguistics
Note:
Pages:
4230–4242
Language:
URL:
https://aclanthology.org/2026.emnlp-industry.250/
DOI:
Bibkey:
Cite (ACL):
S M Masrur Ahmed and Jaspal Subhlok. 2026. Cite or Decline: A Strict Course-Grounded Chatbot for STEM Lecture Videos. In Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing: Industry Track, pages 4230–4242, Budapest, Hungary. Association for Computational Linguistics.
Cite (Informal):
Cite or Decline: A Strict Course-Grounded Chatbot for STEM Lecture Videos (Ahmed & Subhlok, EMNLP 2026)
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PDF:
https://aclanthology.org/2026.emnlp-industry.250.pdf