Large Language Model
Aggregation Artifacts in Subjective Tasks Collapse Large Language Models' Posteriors
Chochlakis, Georgios, Potamianos, Alexandros, Lerman, Kristina, Narayanan, Shrikanth
In-context Learning (ICL) has become the primary method for performing natural language tasks with Large Language Models (LLMs). The knowledge acquired during pre-training is crucial for this few-shot capability, providing the model with task priors. However, recent studies have shown that ICL predominantly relies on retrieving task priors rather than "learning" to perform tasks. This limitation is particularly evident in complex subjective domains such as emotion and morality, where priors significantly influence posterior predictions. In this work, we examine whether this is the result of the aggregation used in corresponding datasets, where trying to combine low-agreement, disparate annotations might lead to annotation artifacts that create detrimental noise in the prompt. Moreover, we evaluate the posterior bias towards certain annotators by grounding our study in appropriate, quantitative measures of LLM priors. Our results indicate that aggregation is a confounding factor in the modeling of subjective tasks, and advocate focusing on modeling individuals instead. However, aggregation does not explain the entire gap between ICL and the state of the art, meaning other factors in such tasks also account for the observed phenomena. Finally, by rigorously studying annotator-level labels, we find that it is possible for minority annotators to both better align with LLMs and have their perspectives further amplified.
REEF: Representation Encoding Fingerprints for Large Language Models
Zhang, Jie, Liu, Dongrui, Qian, Chen, Zhang, Linfeng, Liu, Yong, Qiao, Yu, Shao, Jing
Protecting the intellectual property of open-source Large Language Models (LLMs) is very important, because training LLMs costs extensive computational resources and data. Therefore, model owners and third parties need to identify whether a suspect model is a subsequent development of the victim model. To this end, we propose a training-free REEF to identify the relationship between the suspect and victim models from the perspective of LLMs' feature representations. Specifically, REEF computes and compares the centered kernel alignment similarity between the representations of a suspect model and a victim model on the same samples. This training-free REEF does not impair the model's general capabilities and is robust to sequential fine-tuning, pruning, model merging, and permutations. In this way, REEF provides a simple and effective way for third parties and models' owners to protect LLMs' intellectual property together. The code is available at https://github.com/tmylla/REEF. The training process of Large Language Models (LLMs) requires extensive computational resources and time. Therefore, open-source models are usually released with specific licenses (e.g., Apache2.0, and LLaMA 2 Community License (Meta AI, 2023)) to protect their intellectual properties (IPs). Unfortunately, some developers claim to have trained their own LLMs but actually wrapped or fine-tuned based on other base LLMs (e.g., Llama-2 and MiniCPM-V) (OpenBMB, 2023; 01-ai, 2023). It is urgent for model owners and third parties to identify whether the suspect model is a subsequent development of the victim model (e.g., Code-llama trained from Llama-2) or is developed from scratch (e.g., Mistral). The key is to extract unique features (i.e., fingerprints) that can authenticate the victim model. Watermarking methods artificially inject triggers into the victim model to make it generate specific content for identification (Peng et al., 2023a; Xu et al., 2024).
What's New in My Data? Novelty Exploration via Contrastive Generation
Fine-tuning is widely used to adapt language models for specific goals, often leveraging real-world data such as patient records, customer-service interactions, or web content in languages not covered in pre-training. These datasets are typically massive, noisy, and often confidential, making their direct inspection challenging. However, understanding them is essential for guiding model deployment and informing decisions about data cleaning or suppressing any harmful behaviors learned during fine-tuning. In this study, we introduce the task of novelty discovery through generation, which aims to identify novel properties of a fine-tuning dataset by generating examples that illustrate these properties. Our approach, Contrastive Generative Exploration (CGE), assumes no direct access to the data but instead relies on a pre-trained model and the same model after fine-tuning. By contrasting the predictions of these two models, CGE can generate examples that highlight novel characteristics of the fine-tuning data. However, this simple approach may produce examples that are too similar to one another, failing to capture the full range of novel phenomena present in the dataset. We address this by introducing an iterative version of CGE, where the previously generated examples are used to update the pre-trained model, and this updated model is then contrasted with the fully fine-tuned model to generate the next example, promoting diversity in the generated outputs. Our experiments demonstrate the effectiveness of CGE in detecting novel content, such as toxic language, as well as new natural and programming languages. Furthermore, we show that CGE remains effective even when models are fine-tuned using differential privacy techniques.
Combining Entropy and Matrix Nuclear Norm for Enhanced Evaluation of Language Models
Large Language Models (LLMs) have revolutionized the field of natural language processing (NLP) by demonstrating unprecedented capabilities in understanding and generating human-like text. Models such as GPT-4, BERT, and their successors have not only achieved remarkable performance across a variety of tasks but have also extended their utility into multi-modal domains, encompassing vision, audio, and other data types. As these models continue to grow in size and complexity, evaluating their performance accurately and efficiently becomes increasingly critical. Traditional evaluation metrics for LLMs, including perplexity, accuracy, and F1 scores, primarily focus on task-specific outcomes. While these metrics provide valuable insights into a model's ability to perform particular tasks, they often fall short in capturing the underlying representational dynamics and information compression capabilities of the models. Moreover, as LLMs scale, the computational demands of these conventional metrics can become prohibitive, necessitating the development of more sophisticated and scalable evaluation methodologies. Recent advancements have introduced novel metrics that delve deeper into the internal workings of LLMs. One such approach is Diff-eRank Wei et al. [2024], a rank-based metric grounded in information theory and geometric principles.
Analyzing Context Utilization of LLMs in Document-Level Translation
Mohammed, Wafaa, Niculae, Vlad
Large language models (LLM) are increasingly strong contenders in machine translation. We study document-level translation, where some words cannot be translated without context from outside the sentence. We investigate the ability of prominent LLMs to utilize context by analyzing models' robustness to perturbed and randomized document context. We find that LLMs' improved document-translation performance is not always reflected in pronoun translation performance. We highlight the need for context-aware finetuning of LLMs with a focus on relevant parts of the context to improve their reliability for document-level translation.
VLFeedback: A Large-Scale AI Feedback Dataset for Large Vision-Language Models Alignment
Li, Lei, Xie, Zhihui, Li, Mukai, Chen, Shunian, Wang, Peiyi, Chen, Liang, Yang, Yazheng, Wang, Benyou, Kong, Lingpeng, Liu, Qi
As large vision-language models (LVLMs) evolve rapidly, the demand for high-quality and diverse data to align these models becomes increasingly crucial. However, the creation of such data with human supervision proves costly and time-intensive. In this paper, we investigate the efficacy of AI feedback to scale supervision for aligning LVLMs. We introduce VLFeedback, the first large-scale vision-language feedback dataset, comprising over 82K multi-modal instructions and comprehensive rationales generated by off-the-shelf models without human annotations. To evaluate the effectiveness of AI feedback for vision-language alignment, we train Silkie, an LVLM fine-tuned via direct preference optimization on VLFeedback. Silkie showcases exceptional performance regarding helpfulness, visual faithfulness, and safety metrics. It outperforms its base model by 6.9\% and 9.5\% in perception and cognition tasks, reduces hallucination issues on MMHal-Bench, and exhibits enhanced resilience against red-teaming attacks. Furthermore, our analysis underscores the advantage of AI feedback, particularly in fostering preference diversity to deliver more comprehensive improvements. Our dataset, training code and models are available at https://vlf-silkie.github.io.
DiSCo Meets LLMs: A Unified Approach for Sparse Retrieval and Contextual Distillation in Conversational Search
Lupart, Simon, Aliannejadi, Mohammad, Kanoulas, Evangelos
Conversational Search (CS) is the task of retrieving relevant documents from a corpus within a conversational context, combining retrieval with conversational context modeling. With the explosion of Large Language Models (LLMs), the CS field has seen major improvements with LLMs rewriting user queries, accounting for conversational context. However, engaging LLMs at inference time harms efficiency. Current methods address this by distilling embeddings from human-rewritten queries to learn the context modeling task. Yet, these approaches predominantly focus on context modeling, and only treat the contrastive component of the retrieval task within a distillation-independent loss term. To address these limitations, we propose a new distillation method, as a relaxation of the previous objective, unifying retrieval and context modeling. We relax the existing training objectives by distilling similarity scores between conversations and documents, rather than relying solely on representation learning. Our proposed distillation objective allows for more freedom in the representation space and leverages the contrastive nature of document relevance. Through experiments on Learned Sparse Retrieval (LSR) across 5 CS datasets, our approach demonstrates substantial improvements in both in-domain and out-of-domain retrieval performance, outperforming state-of-the-art with gains of up to 6 points in recall for out-of-domain datasets. Additionally, through the relaxation of the objective, we propose a multi-teacher distillation, using multiple LLMs as teachers, yielding additional gains, and outperforming the teachers themselves in in-domain experiments. Finally, analysis of the sparsity of the models reveals that our distillation allows for better control over the sparsity of the trained models.
Automated Genre-Aware Article Scoring and Feedback Using Large Language Models
Wang, Chihang, Dong, Yuxin, Zhang, Zhenhong, Wang, Ruotong, Wang, Shuo, Chen, Jiajing
This paper focuses on the development of an advanced intelligent article scoring system that not only assesses the overall quality of written work but also offers detailed feature-based scoring tailored to various article genres. By integrating the pre-trained BERT model with the large language model Chat-GPT, the system gains a deep understanding of both the content and structure of the text, enabling it to provide a thorough evaluation along with targeted suggestions for improvement. Experimental results demonstrate that this system outperforms traditional scoring methods across multiple public datasets, particularly in feature-based assessments, offering a more accurate reflection of the quality of different article types. Moreover, the system generates personalized feedback to assist users in enhancing their writing skills, underscoring the potential and practical value of automated scoring technologies in educational contexts.
How Do Multilingual Models Remember? Investigating Multilingual Factual Recall Mechanisms
Fierro, Constanza, Foroutan, Negar, Elliott, Desmond, Sรธgaard, Anders
Large Language Models (LLMs) store and retrieve vast amounts of factual knowledge acquired during pre-training. Prior research has localized and identified mechanisms behind knowledge recall; however, it has primarily focused on English monolingual models. The question of how these processes generalize to other languages and multilingual LLMs remains unexplored. In this paper, we address this gap by conducting a comprehensive analysis of two highly multilingual LLMs. We assess the extent to which previously identified components and mechanisms of factual recall in English apply to a multilingual context. Then, we examine when language plays a role in the recall process, uncovering evidence of language-independent and language-dependent mechanisms.
Revisiting SLO and Goodput Metrics in LLM Serving
Wang, Zhibin, Li, Shipeng, Zhou, Yuhang, Li, Xue, Gu, Rong, Cam-Tu, Nguyen, Tian, Chen, Zhong, Sheng
Large language models (LLMs) have achieved remarkable performance and are widely deployed in various applications, while the serving of LLM inference has raised concerns about user experience and serving throughput. Accordingly, service level objectives (SLOs) and goodput-the number of requests that meet SLOs per second-are introduced to evaluate the performance of LLM serving. However, existing metrics fail to capture the nature of user experience. We observe two ridiculous phenomena in existing metrics: 1) delaying token delivery can smooth the tail time between tokens (tail TBT) of a request and 2) dropping the request that fails to meet the SLOs midway can improve goodput. In this paper, we revisit SLO and goodput metrics in LLM serving and propose a unified metric framework smooth goodput including SLOs and goodput to reflect the nature of user experience in LLM serving. The framework can adapt to specific goals of different tasks by setting parameters. We re-evaluate the performance of different LLM serving systems under multiple workloads based on this unified framework and provide possible directions for future optimization of existing strategies. We hope that this framework can provide a unified standard for evaluating LLM serving and foster researches in the field of LLM serving optimization to move in a cohesive direction.