arXiv AI

Layer-Wise Gate-Controlled Prompt Truncation in a Multimodal Chest X-Ray Classifier

The paper presents a layer‑wise gating mechanism for prompt truncation in a multimodal chest X‑ray classifier based on Mixture of Prompt Experts (MoPE). The controller predicts a retention ratio per sample, averages these ratios per mini‑batch, and truncates the static and mixed visual prompts to an integer length, also scaling retained prompts by the individual ratios. In a pilot study, the gated model achieved a best validation accuracy of 0.8996 versus 0.8969 for the fixed‑length baseline, with final values of 0.8963 and 0.8802, while the gate statistics showed a retained length of one token out of a configured maximum of six, reducing the visual sequence from 210 to 200 tokens. "whyItMatters":"The study demonstrates that prompt shortening via a gating strategy can slightly improve validation accuracy in a multimodal chest X‑ray classification task, though it does not yet confirm runtime acceleration or clinical utility."

arXiv AI
Sep 25

Med-AR: Autoregressive Vision-Language Pretraining for Long-Tailed Chest X-Ray Classification and Uncertainty-Aware Evaluation

Med-AR introduces two autoregressive vision‑language models, Med‑AR‑8B and Med‑AR‑2B, pretrained on structured radiology reports, abnormality‑focused text, and region annotations to address long‑tailed chest X‑ray classification. The models outperform existing contrastive, self‑supervised, and supervised encoders—including Med‑CLIP, CheXFound, EVA‑Base, ARK, and BioViL‑T—across PadChest, MIMIC‑CXR, and CheXpert, achieving higher mean AUROC and AUPRC for head, medium, and tail findings and lower excess area under the risk‑coverage curve. Med‑AR also demonstrates improved selective‑prediction performance, with Med‑AR‑8B raising tail‑label mean AUPRC on MIMIC‑CXR from 0.1033 to 0.1441 and Med‑AR‑2B delivering the strongest discrimination on PadChest.

By Janhavi Prabhu, Sahil, Akshay V, Shivam Shukla, Manoj Tadepalli, Preetham Putha
Hugging Face Trending Papers
Sep 4

Cross-dataset transportability of pediatric chest X-ray deep learning across three countries: discrimination, calibration, operating-point failure, and limited-label recovery

The study evaluates a deep‑learning model for pediatric pneumonia detection across three countries, testing not only discrimination but also probability calibration, fixed operating‑point transport, shortcut signals, and limited‑label recoverability. Using a DenseNet121 ensemble trained on Guangzhou data, the model achieved high internal AUROC (0.976) but performance dropped to 0.798 and 0.742 on Bangladeshi and Vietnamese datasets, respectively. Limited‑label adaptation with Platt recalibration restored sensitivity but introduced significant specificity variability, highlighting the need for comprehensive cross‑dataset evaluation.

arXiv Computer Vision
Sep 7

Cross-dataset transportability of pediatric chest X-ray deep learning across three countries: discrimination, calibration, operating-point failure, and limited-label recovery

The study evaluates a deep‑learning model for pediatric pneumonia detection across chest X‑ray datasets from three countries, assessing discrimination, calibration, operating‑point transport, shortcut signals, and limited‑label recovery. Using a frozen DenseNet121 ensemble trained on Guangzhou data, the model achieved high internal AUROC (0.976) but performance dropped when applied zero‑shot to Bangladesh (AUROC 0.798) and Vietnam (AUROC 0.742). Limited‑label adaptation with Platt recalibration restored sensitivity but introduced significant specificity variability, highlighting the need to evaluate multiple performance dimensions in cross‑dataset transport studies.

By Nazim-E-Alam
arXiv AI
Aug 12

RadFusion: Towards Threshold-Controllable Radiology Report Generation

arXiv:2608. 10505v1 Announce Type: new Abstract: Automated radiology report generation is advancing rapidly in response to the shortage of radiologists, yet unlike a perception model, existing generation models offer no control over the sensitivity-specificity trade-off of their diagnostic content.

By Ying Jin, Noel C. F. Codella, John Corring, Mu Wei, Dinei Florencio, Eric Horvitz
arXiv Computer Vision
Aug 27

Targeting the Attention Heads Behind Object Hallucination in LLaVA

The paper investigates why vision‑language models like LLaVA‑1.5‑7B hallucinate objects in captions and proposes a targeted fix. By ranking attention heads whose image attention drops around hallucinated words, the authors identify 32 key heads and apply a head‑sliced LoRA adapter plus an inference‑time grounding controller. On COCO images, this combined method reduces hallucinated captions from 37% to 23% and hallucinated object mentions from 15.6% to 9.6%, while also lowering object recall.

By Armaan Sandhu, Abhilasha Senapati, Hima Kammachi
arXiv Computer Vision
Aug 27

SPARK-SAM: Learning How to Prompt and Respond for Infrared Small Target Segmentation

SPARK‑SAM is a new approach that adapts the Segment‑Anything Model (SAM) for infrared small‑target segmentation by learning target‑domain response knowledge and conditioning the decoder with an image‑conditioned joint self‑prompt state. In experiments on three IRSTD benchmarks, SPARK‑SAM achieves IoU scores of 75.78%, 86.49%, and 68.34% with only 0.726 M additional parameters, outperforming 14 retrained SAM variants. The method combines benchmark‑mask supervision with reliability‑aware response guidance, and ablations show consistent accuracy gains from response guidance and high‑resolution prompt refinement.

By Aji Mao, Zhenming Peng, Bailin Mu, Tian Pu