Large Language Model
OCR Error Post-Correction with LLMs in Historical Documents: No Free Lunches
Kanerva, Jenna, Ledins, Cassandra, Käpyaho, Siiri, Ginter, Filip
Optical Character Recognition (OCR) systems often introduce errors when transcribing historical documents, leaving room for post-correction to improve text quality. This study evaluates the use of open-weight LLMs for OCR error correction in historical English and Finnish datasets. We explore various strategies, including parameter optimization, quantization, segment length effects, and text continuation methods. Our results demonstrate that while modern LLMs show promise in reducing character error rates (CER) in English, a practically useful performance for Finnish was not reached. Our findings highlight the potential and limitations of LLMs in scaling OCR post-correction for large historical corpora.
Learning to Generate Unit Tests for Automated Debugging
Prasad, Archiki, Stengel-Eskin, Elias, Chen, Justin Chih-Yao, Khan, Zaid, Bansal, Mohit
Unit tests (UTs) play an instrumental role in assessing code correctness as well as providing feedback to a large language model (LLM) as it iteratively debugs faulty code, motivating automated test generation. However, we uncover a trade-off between generating unit test inputs that reveal errors when given a faulty code and correctly predicting the unit test output without access to the gold solution. To address this trade-off, we propose UTGen, which teaches LLMs to generate unit test inputs that reveal errors along with their correct expected outputs based on task descriptions and candidate code. We integrate UTGen into UTDebug, a robust debugging pipeline that uses generated tests to help LLMs debug effectively. Since model-generated tests can provide noisy signals (e.g., from incorrectly predicted outputs), UTDebug (i) scales UTGen via test-time compute to improve UT output prediction, and (ii) validates and back-tracks edits based on multiple generated UTs to avoid overfitting. We show that UTGen outperforms UT generation baselines by 7.59% based on a metric measuring the presence of both error-revealing UT inputs and correct UT outputs. When used with UTDebug, we find that feedback from UTGen's unit tests improves pass@1 accuracy of Qwen-2.5 7B on HumanEvalFix and our own harder debugging split of MBPP+ by over 3% and 12.35% (respectively) over other LLM-based UT generation baselines.
Fairness through Difference Awareness: Measuring Desired Group Discrimination in LLMs
Wang, Angelina, Phan, Michelle, Ho, Daniel E., Koyejo, Sanmi
Algorithmic fairness has conventionally adopted a perspective of racial color-blindness (i.e., difference unaware treatment). We contend that in a range of important settings, group difference awareness matters. For example, differentiating between groups may be necessary in legal contexts (e.g., the U.S. compulsory draft applies to men but not women) and harm assessments (e.g., calling a girl a terrorist may be less harmful than calling a Muslim person one). In our work we first introduce an important distinction between descriptive (fact-based), normative (value-based), and correlation (association-based) benchmarks. This distinction is significant because each category requires distinct interpretation and mitigation tailored to its specific characteristics. Then, we present a benchmark suite composed of eight different scenarios for a total of 16k questions that enables us to assess difference awareness. Finally, we show results across ten models that demonstrate difference awareness is a distinct dimension of fairness where existing bias mitigation strategies may backfire.
Theoretical Analysis of KL-regularized RLHF with Multiple Reference Models
Aminian, Gholamali, Asadi, Amir R., Shenfeld, Idan, Mroueh, Youssef
Recent methods for aligning large language models (LLMs) with human feedback predominantly rely on a single reference model, which limits diversity, model overfitting, and underutilizes the wide range of available pre-trained models. Incorporating multiple reference models has the potential to address these limitations by broadening perspectives, reducing bias, and leveraging the strengths of diverse open-source LLMs. However, integrating multiple reference models into reinforcement learning with human feedback (RLHF) frameworks poses significant theoretical challenges, particularly in reverse KL-regularization, where achieving exact solutions has remained an open problem. This paper presents the first \emph{exact solution} to the multiple reference model problem in reverse KL-regularized RLHF. We introduce a comprehensive theoretical framework that includes rigorous statistical analysis and provides sample complexity guarantees. Additionally, we extend our analysis to forward KL-regularized RLHF, offering new insights into sample complexity requirements in multiple reference scenarios. Our contributions lay the foundation for more advanced and adaptable LLM alignment techniques, enabling the effective use of multiple reference models. This work paves the way for developing alignment frameworks that are both theoretically sound and better suited to the challenges of modern AI ecosystems.
INSIGHT: Enhancing Autonomous Driving Safety through Vision-Language Models on Context-Aware Hazard Detection and Edge Case Evaluation
Chen, Dianwei, Zhang, Zifan, Liu, Yuchen, Yang, Xianfeng Terry
Autonomous driving systems face significant challenges in handling unpredictable edge-case scenarios, such as adversarial pedestrian movements, dangerous vehicle maneuvers, and sudden environmental changes. Current end-to-end driving models struggle with generalization to these rare events due to limitations in traditional detection and prediction approaches. To address this, we propose INSIGHT (Integration of Semantic and Visual Inputs for Generalized Hazard Tracking), a hierarchical vision-language model (VLM) framework designed to enhance hazard detection and edge-case evaluation. By using multimodal data fusion, our approach integrates semantic and visual representations, enabling precise interpretation of driving scenarios and accurate forecasting of potential dangers. Through supervised fine-tuning of VLMs, we optimize spatial hazard localization using attention-based mechanisms and coordinate regression techniques. Experimental results on the BDD100K dataset demonstrate a substantial improvement in hazard prediction straightforwardness and accuracy over existing models, achieving a notable increase in generalization performance. This advancement enhances the robustness and safety of autonomous driving systems, ensuring improved situational awareness and potential decision-making in complex real-world scenarios.
QLESS: A Quantized Approach for Data Valuation and Selection in Large Language Model Fine-Tuning
Ananta, Moses, Adilazuarda, Muhammad Farid, Zuhri, Zayd Muhammad Kawakibi, Purwarianti, Ayu, Aji, Alham Fikri
Fine-tuning large language models (LLMs) is often constrained by the computational costs of processing massive datasets. We propose \textbf{QLESS} (Quantized Low-rank Gradient Similarity Search), which integrates gradient quantization with the LESS framework to enable memory-efficient data valuation and selection. QLESS employs a two-step compression process: first, it obtains low-dimensional gradient representations through LoRA-based random projection; then, it quantizes these gradients to low-bitwidth representations. Experiments on multiple LLM architectures (LLaMA, Mistral, Qwen) and benchmarks (MMLU, BBH, TyDiQA) show that QLESS achieves comparable data selection performance to LESS while reducing memory usage by up to 16x. Even 1-bit gradient quantization preserves data valuation quality. These findings underscore QLESS as a practical, scalable approach to identifying informative examples within strict memory constraints.
Breaking Focus: Contextual Distraction Curse in Large Language Models
Huang, Yue, Wang, Yanbo, Xu, Zixiang, Gao, Chujie, Wu, Siyuan, Ye, Jiayi, Chen, Xiuying, Chen, Pin-Yu, Zhang, Xiangliang
Large Language Models (LLMs) (Zhou et al., 2023b) have demonstrated remarkable capabilities across various Natural Language Processing (NLP) tasks, revolutionizing wide downstream applications such as medicine (Zhao et al., 2023), education (Kasneci et al., 2023), and science (Li et al., 2024b; Guo et al., 2023; Huang et al., 2024e). Despite their impressive performance, recent studies have exposed various vulnerabilities in LLMs, including susceptibility to jailbreaking attacks (Zou et al., 2023), hallucination issues (Xu et al., 2024b), and consistency problems (Liang et al., 2024; Huang et al., 2024a). These vulnerabilities highlight the limitations of LLMs in handling nuanced and adversarial scenarios, making it critical to uncover and analyze additional weaknesses to improve their reliability. In this work, we investigate a novel vulnerability termed Contextual Distraction Vulnerability (CDV), where semantically coherent but non-essential contextual additions to a question degrade LLM performance. For instance, a customer service chatbot might miss a refund request hidden in a short story about discovering products through social media influencers. Similarly, a technical query about machine learning could be misunderstood if it's preceded by a student's emotional account of exam preparation anxiety. Unlike adversarial attacks that inject semantically meaningless noise into inputs (Zou et al., 2023; Shi et al., 2024) and distraction brought by long-context input (Bai et al., 2023), for CDV, our study demonstrates that semantically coherent without a long context yet contextually distracting modifications are sufficient to disrupt the decision-making process of even the most advanced LLMs. This vulnerability underscores a critical weakness in LLMs' ability to filter out irrelevant information and prioritize core knowledge, which is essential for robust reasoning. Recent studies have demonstrated the powerful generative capabilities of LLM Xu et al. (2024a); Wu et al. (2024), To systematically investigate this vulnerability, we propose a methodology for
Gradient-Regularized Latent Space Modulation in Large Language Models for Structured Contextual Synthesis
Yotheringhay, Derek, Nightingale, Beatrix, Featherstone, Maximilian, Worthington, Edmund, Ashdown, Hugo
Generating structured textual content requires mechanisms that enforce coherence, stability, and adherence to predefined constraints while maintaining semantic fidelity. Conventional approaches often rely on rule-based heuristics or fine-tuning strategies that lack flexibility and generalizability across diverse tasks. The incorporation of Gradient-Regularized Latent Space Modulation (GRLSM) introduces a novel paradigm for guiding text generation through the application of structured constraints within the latent space. The integration of gradient-based regularization mitigates abrupt variations in latent representations, ensuring a smoother encoding process that enhances structural consistency and logical progression within generated sequences. Comparative evaluations demonstrate that latent space modulation leads to a reduction in perplexity, increased coherence scores, and improved structural alignment across multiple domains. Stability assessments further indicate that the imposition of spectral norm constraints facilitates more controlled variations in generated text, preserving semantic consistency under input perturbations. Empirical results confirm that structured latent space constraints not only refine the organization of generated outputs but also enhance interpretability through more predictable and reliable synthesis patterns. Performance metrics illustrate that the GRLSM framework substantially reduces structural inconsistencies while preserving the generative flexibility inherent in neural models.
Efficiently Integrate Large Language Models with Visual Perception: A Survey from the Training Paradigm Perspective
Ma, Xiaorui, Xie, Haoran, Qin, S. Joe
The integration of vision-language modalities has been a significant focus in multimodal learning, traditionally relying on Vision-Language Pretrained Models. However, with the advent of Large Language Models (LLMs), there has been a notable shift towards incorporating LLMs with vision modalities. Following this, the training paradigms for incorporating vision modalities into LLMs have evolved. Initially, the approach was to integrate the modalities through pretraining the modality integrator, named Single-stage Tuning. It has since branched out into methods focusing on performance enhancement, denoted as Two-stage Tuning, and those prioritizing parameter efficiency, referred to as Direct Adaptation. However, existing surveys primarily address the latest Vision Large Language Models (VLLMs) with Two-stage Tuning, leaving a gap in understanding the evolution of training paradigms and their unique parameter-efficient considerations. This paper categorizes and reviews 34 VLLMs from top conferences, journals, and highly cited Arxiv papers, focusing on parameter efficiency during adaptation from the training paradigm perspective. We first introduce the architecture of LLMs and parameter-efficient learning methods, followed by a discussion on vision encoders and a comprehensive taxonomy of modality integrators. We then review three training paradigms and their efficiency considerations, summarizing benchmarks in the VLLM field. To gain deeper insights into their effectiveness in parameter efficiency, we compare and discuss the experimental results of representative models, among which the experiment of the Direct Adaptation paradigm is replicated. Providing insights into recent developments and practical uses, this survey is a vital guide for researchers and practitioners navigating the efficient integration of vision modalities into LLMs.
Visual Attention Never Fades: Selective Progressive Attention ReCalibration for Detailed Image Captioning in Multimodal Large Language Models
Jung, Mingi, Lee, Saehuyng, Kim, Eunji, Yoon, Sungroh
Detailed image captioning is essential for tasks like data generation and aiding visually impaired individuals. High-quality captions require a balance between precision and recall, which remains challenging for current multimodal large language models (MLLMs). In this work, we hypothesize that this limitation stems from weakening and increasingly noisy visual attention as responses lengthen. To address this issue, we propose SPARC (Selective Progressive Attention ReCalibration), a training-free method that enhances the contribution of visual tokens during decoding. SPARC is founded on three key observations: (1) increasing the influence of all visual tokens reduces recall; thus, SPARC selectively amplifies visual tokens; (2) as captions lengthen, visual attention becomes noisier, so SPARC identifies critical visual tokens by leveraging attention differences across time steps; (3) as visual attention gradually weakens, SPARC reinforces it to preserve its influence. Our experiments, incorporating both automated and human evaluations, demonstrate that existing methods improve the precision of MLLMs at the cost of recall. In contrast, our proposed method enhances both precision and recall with minimal computational overhead.