arXiv Computer Vision

When Models Misread Ink: Auditing VLMs for Arabic Calligraphy Recognition

The paper audits 12 vision‑language models on a 1,195‑image Arabic calligraphy benchmark, testing numeric, visual‑cue, and Diwani‑first prompts. Accuracy peaks at 60.9% for closed/API models and 47.2% for open‑weight models, but many models collapse to a single default label (often Thuluth) far above the majority‑class baseline. Prompting improves performance unevenly, with visual cues boosting some models by over 10 points while others suffer, and foregrounding Diwani often shifts but does not eliminate the default bias.

arXiv AI
Sep 16

Same Answer, Different Representations: Hidden instability in VLMs

arXiv:2602.06652v2 Announce Type: replace Abstract: The robustness of Vision Language Models (VLMs) is commonly assessed through output-level invariance, implicitly assuming that stable predictions r...

By Farooq Ahmad Wani, Alessandro Suglia, Rohit Saxena, Aryo Pradipta Gema, Wai-Chung Kwan, Fazl Barez, Maria Sofia Bucarelli, Fabrizio Silvestri, Pasquale Minervini
arXiv Computer Vision
Oct 9

Multimodal Large Language Models as Image Classifiers

The paper investigates how evaluation protocols and ground‑truth quality affect the classification performance of Multimodal Large Language Models (MLLMs). It identifies and corrects key issues such as discarded out‑of‑list outputs, inflated distractor choices, and poor open‑world mapping, and shows that design choices like batch size, image ordering, and text encoder selection significantly influence accuracy. Using a multilabel reannotation of 625 ImageNet‑1k classes (ReGT), the study finds that corrected labels can boost MLLM performance by up to 10.8%, narrowing the gap with supervised models, and demonstrates that MLLMs can assist human annotators in about half of difficult cases.

By Nikita Kisel, Illia Volkov, Klara Janouskova, Jiri Matas
arXiv Computation and Language
Sep 24

PRISM-VLM: A Multi-Axis Discriminative Benchmark for Compact Vision-Language Models

PRISM‑VLM is a new benchmark for compact vision‑language models that evaluates each item across seven axes—task quality, behavioral robustness, and capability bottlenecks—rather than collapsing performance into a single accuracy score. It aggregates these axes into a single PScore while also providing per‑axis profiles, revealing differences that single‑axis benchmarks miss, such as sycophancy. The benchmark draws on items from fifteen public datasets and will be released with its full pipeline, prompts, and annotations.

By Sanghee Park, Kee-Eung Kim
arXiv AI
Aug 25

WildHandBench: A Benchmark for Handwritten Text Understanding that Challenges MLLMs and Humans

WildHandBench is a new benchmark comprising 500 handwritten documents that span free text, tables, and formulas across four languages and nine real‑world scenarios. It introduces a Prior‑Driven Error (PDE) metric to assess whether mistakes stem from language priors rather than visual cues. In tests of 18 state‑of‑the‑art models, the best achieves only 71.85% accuracy, while humans reach 77.09%, and model errors are largely prior‑driven (63‑91%) compared to human errors (49%).

By Jun Zhang, Qiao Zhao, Cheng Cui, Jianying Qu, Zhongkai Sun, Jianwen Yang, Changda Zhou, ZhuoXin Liu, Shubin Han
arXiv AI
Aug 26

Seeing vs. Believing: Evaluating the Language Bias of Open-Source MLLMs in Counter-Intuitive Scenes

The paper introduces CAIT, a benchmark of 400 synthetic scenes featuring counter‑intuitive actions that challenge multimodal large language models (MLLMs). Human participants and proprietary models like Claude and Gemini perform well, but standard open‑source instruction‑tuned MLLMs fail, largely due to a strong language prior that overrides contradictory visual evidence. The study shows that Chain‑of‑Thought reasoning can help but introduces new issues, while targeted fine‑tuning and structured prompting can reduce reliance on language priors and improve visual grounding.

By Chen Ling, Tongwei Zhang, Hanqian Li, Nai Ding