Soft Prompts for Adapting LLMs to Cultural Commonsense Knowledge
Gabrielle Le Bellier, Marine Carpuat, Benoît Sagot, Chloé Clavel
Abstract
Large Language Models (LLMs) show unbalanced knowledge of cultures across the globe, favoring high-resource cultures over low-resource ones. A possible way to tackle this issue is to fine-tune LLMs on culturally specific data. However, fine-tuning recent LLMs requires high computational resources as well as memory storage, which triggered the development of parameter-efficient fine-tuning (PEFT) approaches, the most widespread being LoRA. In this article, we investigate the use of another class of PEFT approaches, namely soft prompt methods (prompt-tuning and prefix-tuning), to improve LLMs’ cultural knowledge across diverse cultures. We focus on cultural alignment on Multiple-Choice Questions of cultural commonsense knowledge. On this task with limited fine-tuning data, we show that soft-prompt-based methods outperform LoRA in comparable settings. Moreover, the trained soft prompts are interpretable and capture similarities between cultures.- Anthology ID:
- 2026.c3nlp-1.6
- Volume:
- Proceedings of the 4th Workshop on Cross-Cultural Considerations in NLP (C3NLP 2026)
- Month:
- July
- Year:
- 2026
- Address:
- San Diego, California, United States
- Editors:
- Vinodkumar Prabhakaran, Sunipa Dev, Luciana Benotti, Daniel Hershcovich, Yong Cao, Li Zhou, BOlei Ma, Ife Adebara
- Venues:
- C3NLP | WS
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 76–100
- Language:
- URL:
- https://preview.aclanthology.org/ingest-acl-workshops/2026.c3nlp-1.6/
- DOI:
- Cite (ACL):
- Gabrielle Le Bellier, Marine Carpuat, Benoît Sagot, and Chloé Clavel. 2026. Soft Prompts for Adapting LLMs to Cultural Commonsense Knowledge. In Proceedings of the 4th Workshop on Cross-Cultural Considerations in NLP (C3NLP 2026), pages 76–100, San Diego, California, United States. Association for Computational Linguistics.
- Cite (Informal):
- Soft Prompts for Adapting LLMs to Cultural Commonsense Knowledge (Bellier et al., C3NLP 2026)
- PDF:
- https://preview.aclanthology.org/ingest-acl-workshops/2026.c3nlp-1.6.pdf