A Rigorous Evaluation of LLM Data Generation Strategies for Low-Resource Languages

Tatiana Anikina, Jan Cegin, Jakub Simko, Simon Ostermann


Abstract
Large Language Models (LLMs) are increasingly used to generate synthetic textual data for training smaller specialized models. However, a comparison of various generation strategies for low-resource language settings is lacking. While various prompting strategies have been proposed—such as demonstrations, label-based summaries, and self-revision—their comparative effectiveness remains unclear, especially for low-resource languages. In this paper, we systematically evaluate the performance of these generation strategies and their combinations across 11 typologically diverse languages, including several extremely low-resource ones. Using three NLP tasks and four open-source LLMs, we assess downstream model performance on generated versus gold-standard data. Our results show that strategic combinations of generation methods — particularly target-language demonstrations with LLM-based revisions — yield strong performance, narrowing the gap with real data to as little as 5% in some settings. We also find that smart prompting techniques can reduce the advantage of larger LLMs, highlighting efficient generation strategies for synthetic data generation in low-resource scenarios with smaller models.
Anthology ID:
2025.emnlp-main.418
Volume:
Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing
Month:
November
Year:
2025
Address:
Suzhou, China
Editors:
Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
Venue:
EMNLP
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Publisher:
Association for Computational Linguistics
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Pages:
8293–8314
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URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.418/
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Cite (ACL):
Tatiana Anikina, Jan Cegin, Jakub Simko, and Simon Ostermann. 2025. A Rigorous Evaluation of LLM Data Generation Strategies for Low-Resource Languages. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 8293–8314, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
A Rigorous Evaluation of LLM Data Generation Strategies for Low-Resource Languages (Anikina et al., EMNLP 2025)
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