Topic · Multimodal
arxiv arXiv cs.LG · 10d ago

Vision-language models don't always need images for chest X-ray accuracy

A causal audit shows that many vision-language models achieve high chest radiograph accuracy without using images. Text-only models match multimodal models in performance and outperform them in grounding, with accuracy and confidence flags only appearing when image use occurs. These findings suggest that accuracy alone is insufficient to validate clinical deployment, and grounding must be assessed.

arxiv arXiv cs.CL · 10d ago

Visuals Lie, Consistency Speaks: Disentangling Spatial Attention from Reliability in Vision-Language Models

A study challenges the assumption that visual attention signals reliability in vision-language models. It finds near-zero correlation between spatial attention and accuracy, showing instead that self-consistency across reasoning paths is a stronger predictor of truth. Reliability is better explained by generation dynamics and internal state distributions, not visual attention patterns.

arxiv arXiv cs.CL · 11d ago

ContextRL: Context-Aware RL for LLMs

ContextRL introduces an indirect auxiliary objective to improve long-horizon reasoning and multimodal performance in LLMs. It rewards models for selecting the context that supports a query-answer pair, using contrastive context data from coding agent trajectories and image-based visual questions. ContextRL achieves +2.2% and +1.8% gains over standard methods on long-horizon and visual QA benchmarks, with gains attributed to the selection objective, not data augmentation.

arxiv arXiv cs.AI · 11d ago

BinTrack: Open-Source Spatial QA with Binary Trajectory Search

BinTrack is a fully open-source spatial question answering agent that uses binary search over a robot's trajectory to locate answers. It achieves up to 22.8% higher accuracy than other open-source methods and matches closed-source model performance on the most challenging global category of the SpaceLocQA benchmark. The system also offers over 1.5x faster inference and introduces GangnamLoop, a real-world outdoor benchmark collected with a quadruped robot.

arxiv arXiv cs.LG · 8d ago

De-biased VLM-as-3D-Judge Protocol for Furniture Generation

A de-biased VLM-based judge protocol specializes TRELLIS on furniture generation using lightweight adaptation. The protocol addresses failure modes like image overload and geometry-hiding, with calibration showing 0.83–1.0 win rates and base-vs-base symmetry at 0.5. Among six adaptation methods, conditioner repair under severe degradation achieves parity with the base model, while no method exceeds a 65% win-rate target.

arxiv arXiv cs.CL · 8d ago

NEST: Dataset for Narrative Event Structures in Long Videos

NEST introduces a dataset of 1005 full-length movies, each annotated with 102 multimodal narrative events grounded in visual, dialogue, and audio content. The dataset captures event relationships such as temporal ordering, hierarchy, and long-range dependencies, with benchmark tasks showing low performance in event detection and localization, and higher performance in event relation extraction after fine-tuning.