Method
RLVR rewards typically check only the final answer, not whether it came from the image or from language priors and dataset shortcuts. EVAN masks the visual evidence a question needs, lets the current policy answer without it, and penalizes plausible wrong answers under the clean image. EVAN-8B is trained with DAPO on ViRL39K. The GitHub repository has the full method, data pipeline, and training scripts.
Results
Accuracy (%) from Table 1 of the paper, with sampling at temperature 1.0. DAPO uses the same data and training recipe without EVAN.
Table with columns: Model, Geo3K, MathVista, MathVerse, We-Math, DynaMath, MathVision, MMK12, MMMU-Pro, LogicVista, Avg.| Model | Geo3K | MathVista | MathVerse | We-Math | DynaMath | MathVision | MMK12 | MMMU-Pro | LogicVista | Avg. |
|---|
| Qwen3-VL-8B-Instruct | 65.2 | 68.7 | 69.4 | 77.2 | 73.4 | 38.0 | 69.1 | 40.3 | 61.3 | 62.5 |
| DAPO | 74.6 | 71.9 | 84.0 | 83.9 | 76.9 | 56.7 | 84.1 | 52.3 | 62.4 | 71.9 |
| EVAN-8B | 76.6 | 74.9 | 85.0 | 84.9 | 77.6 | 57.0 | 85.0 | 52.0 | 63.6 | 73.0 |
Usage
Requires transformers>=4.57, accelerate, and torchvision. Add the instruction below after the question, as in training. The default generation config holds the sampling settings we used for evaluation.
from transformers import AutoModelForImageTextToText, AutoProcessor model_id = "DawnLiu/EVAN-8B"model = AutoModelForImageTextToText.from_pretrained(model_id, dtype="auto", device_map="auto")processor = AutoProcessor.from_pretrained(model_id) question = "Which object is the largest?"prompt = ( f"{question}\n\n" "You first think through the reasoning process as an internal monologue, enclosed within <think> </think> tags. Then, provide your final answer enclosed within \\boxed{}.")messages = [ { "role": "user", "content": [ {"type": "image", "image": "path/to/image.png"}, {"type": "text", "text": prompt}, ], }]inputs = processor.apply_chat_template( messages, tokenize=True, add_generation_prompt=True, return_dict=True, return_tensors="pt").to(model.device)output = model.generate(**inputs)print(processor.decode(output[0, inputs["input_ids"].shape[1]:], skip_special_tokens=True))
Citation
@misc{liu2026grounding, title = {Grounding Multimodal Reasoning with Evidence-Ablated Negatives}, author = {Chenxi Liu and Tianyi Xiong and Yanshuo Chen and Heng Huang}, year = {2026}, eprint = {2610.39237}, archivePrefix = {arXiv}, url = {https://arxiv.org/abs/2610.39237},}
License
Apache 2.0, the same as Qwen3-VL-8B-Instruct. Relative to the base model, the weights were changed by RL training with EVAN, generation_config.json sets our evaluation sampling defaults, and the other configuration, tokenizer, and processor files were re-saved (with dtype set to bfloat16 in config.json).