Revisiting Chain-of-Thought Prompting: Zero-shot Can Be Stronger than Few-shot
Xiang Cheng, Chengyan Pan, Minjun Zhao, Deyang Li, Fangchao Liu, Xinyu Zhang, Xiao Zhang, Yong Liu
Abstract
In-Context Learning (ICL) is an essential emergent ability of Large Language Models (LLMs), and recent studies introduce CoT to exemplars of ICL to enhance the reasoning capability, especially in mathematics tasks. However, given the continuous advancement of model capabilities, it remains unclear whether CoT exemplars still benefit recent, stronger models in such tasks. Through systematic experiments, we find that for recent strong models such as the Qwen2.5 series, adding traditional CoT exemplars does not improve reasoning performance compared to Zero-Shot CoT. Instead, their primary function is to align the output format with human expectations. We further investigate the effectiveness of enhanced CoT exemplars, constructed using answers from advanced models such as Qwen2.5-Max and DeepSeek-R1. Experimental results indicate that these enhanced exemplars still fail to improve the model’s reasoning performance. Further analysis reveals that models tend to ignore the exemplars and focus primarily on the instructions, leading to no observable gain in reasoning ability. Overall, our findings highlight the limitations of the current ICL+CoT framework in mathematical reasoning, calling for a re-examination of the ICL paradigm and the definition of exemplars.- Anthology ID:
- 2025.findings-emnlp.729
- Volume:
- Findings of the Association for Computational Linguistics: EMNLP 2025
- Month:
- November
- Year:
- 2025
- Address:
- Suzhou, China
- Editors:
- Christos Christodoulopoulos, Tanmoy Chakraborty, Carolyn Rose, Violet Peng
- Venue:
- Findings
- SIG:
- Publisher:
- Association for Computational Linguistics
- Note:
- Pages:
- 13533–13554
- Language:
- URL:
- https://preview.aclanthology.org/author-page-yu-wang-polytechnic/2025.findings-emnlp.729/
- DOI:
- 10.18653/v1/2025.findings-emnlp.729
- Cite (ACL):
- Xiang Cheng, Chengyan Pan, Minjun Zhao, Deyang Li, Fangchao Liu, Xinyu Zhang, Xiao Zhang, and Yong Liu. 2025. Revisiting Chain-of-Thought Prompting: Zero-shot Can Be Stronger than Few-shot. In Findings of the Association for Computational Linguistics: EMNLP 2025, pages 13533–13554, Suzhou, China. Association for Computational Linguistics.
- Cite (Informal):
- Revisiting Chain-of-Thought Prompting: Zero-shot Can Be Stronger than Few-shot (Cheng et al., Findings 2025)
- PDF:
- https://preview.aclanthology.org/author-page-yu-wang-polytechnic/2025.findings-emnlp.729.pdf