Chaim Baskin
Author directory2026
Step-Wise Refusal Dynamics in Autoregressive and Diffusion Language Models
Eliron Rahimi | Elad Hirshel | Amit LeVi | Rom Himelstein | Avi Mendelson | Chaim Baskin
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Eliron Rahimi | Elad Hirshel | Amit LeVi | Rom Himelstein | Avi Mendelson | Chaim Baskin
Proceedings of the 2026 Conference on Empirical Methods in Natural Language Processing
Diffusion language models (DLMs) have recently emerged as a competitive alternative to autoregressive (AR) models, offering parallel decoding, competitive generation quality, and initial evidence of improved jailbreak robustness. Despite this progress, the role of sampling mechanisms in shaping refusal behavior remains poorly understood. To address this gap, we present a comprehensive study of step-wise refusal dynamics. We show that diffusion remasking can promote recovery from harmful intermediate generations, provide evidence that this behavior is tied to the sampling mechanism, and demonstrate that switching from AR to diffusion sampling improves jailbreak robustness, including under fixed model weights. To capture generation dynamics not observable at the text level, we propose the Step-Wise Refusal Internal Dynamics (SRI) signal. Consistent with our text-level findings, SRI shows that recovery fails primarily under AR sampling, with these failures often appearing anomalous relative to harmless generations in the SRI space. Based on this observation, we show that SRI enables a simple jailbreak detector that does not modify inference and generalizes to unseen attacks by training only on benign SRI signals. Our evaluation shows that this detector matches or outperforms existing jailbreak detection baselines while adding negligible overhead.
Look Where It Matters: High-Resolution Crops Retrieval for Efficient VLMs
Nimrod Shabtay | Moshe Kimhi | Sivan Harary | Artem Spector | Ehud Rivlin | Chaim Baskin | Raja Giryes | Eli Schwartz
The Proceedings of Workshop on Document Intelligence and Understanding
Nimrod Shabtay | Moshe Kimhi | Sivan Harary | Artem Spector | Ehud Rivlin | Chaim Baskin | Raja Giryes | Eli Schwartz
The Proceedings of Workshop on Document Intelligence and Understanding
Vision-language models (VLMs) typically process images at a native high-resolution, forcing a trade-off between accuracy and computational efficiency: high-resolution inputs capture fine details but incur significant computational costs, while low-resolution inputs advocate for efficiency, they potentially miss critical visual information, specifically OCR related. We present AwaRes, a spatial-on-demand framework that resolves this accuracy–efficiency trade-off by operating on a low-resolution global view and using tool-calling to retrieve only high-resolution segment needed for a given query, rather than escalating to the full image. We construct this supervision automatically: a judge compares low- vs. high-resolution answers to label whether cropping is needed, and an oracle grounding model localizes the evidence for the correct answer, which we map to a discrete crop set to form multi-turn tool-use trajectories. We train our framework with SFT followed by multi-turn GRPO with a composite reward that combines semantic answer correctness with explicit crop-cost penalties. AwaRes provides a practical, deployment-friendly path to high-detail VLM reasoning under tight compute budgets.
CARES: Context-Aware Resolution Selector for VLMs
Moshe Kimhi | Nimrod Shabtay | Raja Giryes | Chaim Baskin | Eli Schwartz
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Moshe Kimhi | Nimrod Shabtay | Raja Giryes | Chaim Baskin | Eli Schwartz
Proceedings of the 64th Annual Meeting of the Association for Computational Linguistics (Volume 1: Long Papers)
Large vision–language models (VLMs) commonly process images at native or high resolution to remain effective across tasks. This inflates visual tokens to 97-99% of total tokens, resulting in high compute and latency, even when low-resolution images would suffice. We introduce CARES—a Context-Aware Resolution Selector, a lightweight preprocessing module that, given an image–query pair, predicts the minimal sufficient input resolution. CARES uses a compact VLM (350M) to extract features and predict when a target pretrained VLM’s response converges to its peak ability to answer correctly. Though trained as a discrete classifier over a set of optional resolutions, CARES interpolates continuous resolutions at inference for fine-grained control. Across five multimodal benchmarks spanning documents and natural images, as well as diverse target VLMs, CARES preserves task performance while reducing compute by up to 80%.
2025
DEPTH: Discourse Education through Pre-Training Hierarchically
Zachary Elisha Bamberger | Ofek Glick | Chaim Baskin | Yonatan Belinkov
Proceedings of the 10th Workshop on Representation Learning for NLP (RepL4NLP-2025)
Zachary Elisha Bamberger | Ofek Glick | Chaim Baskin | Yonatan Belinkov
Proceedings of the 10th Workshop on Representation Learning for NLP (RepL4NLP-2025)
Jailbreak Attack Initializations as Extractors of Compliance Directions
Amit LeVi | Rom Himelstein | Yaniv Nemcovsky | Avi Mendelson | Chaim Baskin
Findings of the Association for Computational Linguistics: EMNLP 2025
Amit LeVi | Rom Himelstein | Yaniv Nemcovsky | Avi Mendelson | Chaim Baskin
Findings of the Association for Computational Linguistics: EMNLP 2025
Safety-aligned LLMs respond to prompts with either compliance or refusal, each corresponding to distinct directions in the model’s activation space. Recent studies have shown that initializing attacks via self-transfer from other prompts significantly enhances their performance. However, the underlying mechanisms of these initializations remain unclear, and attacks utilize arbitrary or hand-picked initializations. This work presents that each gradient-based jailbreak attack and subsequent initialization gradually converge to a single compliance direction that suppresses refusal, thereby enabling an efficient transition from refusal to compliance. Based on this insight, we propose CRI, an initialization framework that aims to project unseen prompts further along compliance directions. We demonstrate our approach on multiple attacks, models, and datasets, achieving an increased attack success rate (ASR) and reduced computational overhead, highlighting the fragility of safety-aligned LLMs.