Beyond Generation: Multi-Hop Reasoning for Factual Accuracy in Vision-Language Models
Shamima Hossain
TL;DR
The paper tackles factual inaccuracies in Visual Language Models by introducing a knowledge-guided, multi-hop reasoning framework that links visual perception to external knowledge graphs. The framework decomposes verification into hops: visual recognition, KG traversal, and fact-based caption refinement, and supports three knowledge representations (triple-based, hierarchical trees, bullet-points). Empirical results on a landmark-focused dataset show a substantial reduction in hallucinations—approximately thirty-two percent—along with improved factual consistency and interpretable reasoning traces. The work demonstrates the viability and potential of integrating external knowledge for reliable multimodal systems and sets the stage for scalable, knowledge-grounded captioning.
Abstract
Visual Language Models (VLMs) are powerful generative tools but often produce factually inaccurate outputs due to a lack of robust reasoning capabilities. While extensive research has been conducted on integrating external knowledge for reasoning in large language models (LLMs), such efforts remain underexplored in VLMs, where the challenge is compounded by the need to bridge multiple modalities seamlessly. This work introduces a framework for knowledge-guided reasoning in VLMs, leveraging structured knowledge graphs for multi-hop verification using image-captioning task to illustrate our framework. Our approach enables systematic reasoning across multiple steps, including visual entity recognition, knowledge graph traversal, and fact-based caption refinement. We evaluate the framework using hierarchical, triple-based and bullet-point based knowledge representations, analyzing their effectiveness in factual accuracy and logical inference. Empirical results show that our approach improves factual accuracy by approximately 31% on preliminary experiments on a curated dataset of mixtures from Google Landmarks v2, Conceptual captions and Coco captions revealing key insights into reasoning patterns and failure modes. This work demonstrates the potential of integrating external knowledge for advancing reasoning in VLMs, paving the way for more reliable and knowledgable multimodal systems.
