COCO-Tree: Compositional Hierarchical Concept Trees for Enhanced Reasoning in Vision-Language Models

Sanchit Sinha, Guangzhi Xiong, Aidong Zhang


Abstract
Compositional reasoning remains a persistent weakness of modern vision language models (VLMs): they often falter when a task hinges on understanding how multiple objects, attributes, and relations interact within an image. Multiple research works have attempted to improve compositionality performance by creative tricks such as improving prompt structure, chain of thought reasoning, etc. A more recent line of work attempts to impart additional reasoning in VLMs using well-trained Large Language Models (LLMs), which are far superior in linguistic understanding than VLMs to compensate for the limited linguistic prowess of VLMs. However, these approaches are either resource-intensive or do not provide an interpretable reasoning process. In this paper, we present “COCO-Tree” - a novel approach that augments VLM outputs with carefully designed neurosymbolic concept trees learned from LLMs to improve VLM’s linguistic reasoning. COCO-Tree’s beam search-inspired reasoning process boosts compositionality performance and provides a rationale behind VLM predictions. Empirical results on four compositionality benchmarks, Winoground, EqBench, ColorSwap, and SugarCrepe, in seven different open-source VLMs with varying sizes, demonstrate that COCO-Tree significantly improves compositional generalization by 5-10% over baselines.
Anthology ID:
2025.emnlp-main.135
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:
2695–2711
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URL:
https://preview.aclanthology.org/ingest-emnlp/2025.emnlp-main.135/
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Cite (ACL):
Sanchit Sinha, Guangzhi Xiong, and Aidong Zhang. 2025. COCO-Tree: Compositional Hierarchical Concept Trees for Enhanced Reasoning in Vision-Language Models. In Proceedings of the 2025 Conference on Empirical Methods in Natural Language Processing, pages 2695–2711, Suzhou, China. Association for Computational Linguistics.
Cite (Informal):
COCO-Tree: Compositional Hierarchical Concept Trees for Enhanced Reasoning in Vision-Language Models (Sinha et al., EMNLP 2025)
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