← Search

Bei Li

41 accepted papers

2026

GRAM-R²: Self-Training Generative Foundation Reward Models for Reward Reasoning

AAAI 2026technical

Major progress in reward modeling over recent years has been driven by a paradigm shift from task-specific designs to generalist reward models. Despite this trend, developing effective reward models remains a fundamental challenge: the heavy reliance on large-scale labeled preference data. Pre-train

Cited by 0SourcePDFScholar
2026

MSRL: Scaling Generative Multimodal Reward Modeling via Multi-Stage Reinforcement Learning

CVPR 2026

Recent advances in multimodal reward modeling have been largely driven by a paradigm shift from discriminative to generative approaches. Building on this progress, recent studies have further employed reinforcement learning with verifiable rewards (RLVR) to enhance multimodal reward models (MRMs). D

Cited by 0SourcecodeScholar
2026

Probing Preference Representations: A Multi-Dimensional Evaluation and Analysis Method for Reward Models

AAAI 2026technical

Previous methods evaluate reward models by testing them on a fixed pairwise ranking test set, but they typically do not provide performance information on each preference dimension. In this work, we address the evaluation challenge of reward models by probing preference representations. To confirm t

Cited by 0SourcePDFScholar
2026

SageLM: A Multi-aspect and Explainable Large Language Model for Speech Judgement

AAAI 2026technical

Speech-to-Speech (S2S) Large Language Models (LLMs) are foundational to natural human-computer interaction, enabling end-to-end spoken dialogue systems. However, evaluating these models remains a fundamental challenge. We propose SageLM, an end-to-end, multi-aspect, and explainable speech LLM for co

Cited by 0SourcePDFScholar
2026

SpanNorm: Reconciling Training Stability and Performance in Deep Transformers

ICML 2026poster

The success of Large Language Models (LLMs) hinges on the stable training of deep Transformer architectures. A critical design choice is the placement of normalization layers, leading to a fundamental trade-off: the ''PreNorm'' architecture ensures training stability at the cost of potential perform…

Cited by 0SourceScholar
2026

Tuning Medical Foundation Models for Inner Ear Temporal CT Analysis with Plug-and-play Domain Knowledge Aggregator

AAAI 2026technical

High-resolution computed tomography (CT) is essential for diagnosing hearing loss and planning interventions such as cochlear implantation, as it provides detailed visualization of inner-ear anatomy. This paper focuses on advancing AI-based analysis of inner-ear CT scans to support clinical decision

Cited by 0SourcePDFScholar
2025

Beyond Decoder-only: Large Language Models Can be Good Encoders for Machine Translation

ACL 2025finding

The field of neural machine translation (NMT) has changed with the advent of large language models (LLMs). Much of the recent emphasis in natural language processing (NLP) has been on modeling machine translation and many other problems using a single pre-trained Transformer decoder, while encoder-d…

2025

Disentangling Preference Representation and Text Generation for Efficient Individual Preference Alignment

COLING 2025main

Aligning Large Language Models (LLMs) with general human preferences has been proved crucial in improving the interaction quality between LLMs and human. However, human values are inherently diverse among different individuals, making it insufficient to align LLMs solely with general preferences. To…

2025

Earlier Tokens Contribute More: Learning Direct Preference Optimization From Temporal Decay Perspective

ICLR 2025poster

Direct Preference Optimization (DPO) has gained attention as an efficient alternative to reinforcement learning from human feedback (RLHF) for aligning large language models (LLMs) with human preferences. Despite its advantages, DPO suffers from a length bias, generating responses longer than those…

2025

GRAM: A Generative Foundation Reward Model for Reward Generalization

ICML 2025poster

In aligning large language models (LLMs), reward models have played an important role, but are standardly trained as discriminative models and rely only on labeled human preference data. In this paper, we explore methods that train reward models using both unlabeled and labeled data. Building on t…

Cited by 0SourcePDFScholar
2025

IIET: Efficient Numerical Transformer via Implicit Iterative Euler Method

EMNLP 2025

High-order numerical methods enhance Transformer performance in tasks like NLP and CV, but introduce a performance-efficiency trade-off due to increased computational overhead. Our analysis reveals that conventional efficiency techniques, such as distillation, can be detrimental to the performance o

2025

Language-Specific Layer Matters: Efficient Multilingual Enhancement for Large Vision-Language Models

EMNLP 2025

Large vision-language models (LVLMs) have demonstrated exceptional capabilities in understanding visual information with human languages but also exhibit an imbalance in multilingual capabilities. In this work, we delve into the multilingual working pattern of LVLMs and identify a salient correlatio

2025

MRO: Enhancing Reasoning in Diffusion Language Models via Multi-Reward Optimization

NeurIPS 2025poster

Recent advances in diffusion language models (DLMs) have presented a promising alternative to traditional autoregressive large language models (LLMs). However, DLMs still lag behind LLMs in reasoning performance, especially as the number of denoising steps decreases. Our analysis reveals that this s…

Cited by 0SourceScholar
2025

Optimizing Speech Multi-View Feature Fusion through Conditional Computation

ICASSP 2025accepted

Recent advancements have highlighted the efficacy of self-supervised learning (SSL) features in various speech-related tasks, providing lightweight and versatile multi-view speech representations. However, our study reveals that while SSL features expedite model convergence, they conflict with tradi…

Cited by 0SourceScholar
2025

ReMamba: Equip Mamba with Effective Long-Sequence Modeling

EMNLP 2025

While the Mamba architecture demonstrates superior inference efficiency and competitive performance on short-context natural language processing (NLP) tasks, empirical evidence suggests its capacity to comprehend long contexts is limited compared to transformer-based models. In this study, we invest

2025

SLAM: Towards Efficient Multilingual Reasoning via Selective Language Alignment

COLING 2025main

Despite the significant improvements achieved by large language models (LLMs) in English reasoning tasks, these models continue to struggle with multilingual reasoning. Recent studies leverage a full-parameter and two-stage training paradigm to teach models to first understand non-English questions…

2025

Selecting Demonstrations for Many-Shot In-Context Learning via Gradient Matching

ACL 2025finding

In-Context Learning (ICL) empowers Large Language Models (LLMs) for rapid task adaptation without Fine-Tuning (FT), but its reliance on demonstration selection remains a critical challenge. While many-shot ICL shows promising performance through scaled demonstrations, the selection method for many-s…

2025

TCPO: Thought-Centric Preference Optimization for Effective Embodied Decision-making

EMNLP 2025

Using effective generalization capabilities of vision language models (VLMs) in context-specific dynamic tasks for embodied artificial intelligence remains a significant challenge. Although supervised fine-tuned models can better align with the real physical world, they still exhibit sluggish respon

Cited by 0SourcePDFScholar
2024

3AM: An Ambiguity-Aware Multi-Modal Machine Translation Dataset

COLING 2024main

Multimodal machine translation (MMT) is a challenging task that seeks to improve translation quality by incorporating visual information. However, recent studies have indicated that the visual information provided by existing MMT datasets is insufficient, causing models to disregard it and overestim…

2024

Clustering and Ranking: Diversity-preserved Instruction Selection through Expert-aligned Quality Estimation

EMNLP 2024main

With contributions from the open-source community, a vast amount of instruction tuning (IT) data has emerged. Given the significant resource allocation required by training and evaluating models, it is advantageous to have an efficient method for selecting high-quality IT data. However, existing met…

2024

CodeAgent: Autonomous Communicative Agents for Code Review

EMNLP 2024main

Code review, which aims at ensuring the overall quality and reliability of software, is a cornerstone of software development. Unfortunately, while crucial, Code review is a labor-intensive process that the research community is looking to automate. Existing automated methods rely on single input-ou…

2024

Connecting Large Language Models with Evolutionary Algorithms Yields Powerful Prompt Optimizers

ICLR 2024poster

Large Language Models (LLMs) excel in various tasks, but they rely on carefully crafted prompts that often demand substantial human effort. To automate this process, in this paper, we propose a novel framework for discrete prompt optimization, called EvoPrompt, which borrows the idea of evolutionary…

Cited by 0SourcePDFScholar
2024

ESRL: Efficient Sampling-Based Reinforcement Learning for Sequence Generation

AAAI 2024technical

Applying Reinforcement Learning (RL) to sequence generation models enables the direct optimization of long-term rewards (e.g., BLEU and human feedback), but typically requires large-scale sampling over a space of action sequences. This is a computational challenge as presented by the practice of seq…

2024

Forgetting Curve: A Reliable Method for Evaluating Memorization Capability for Long-Context Models

EMNLP 2024main

Numerous recent works target to extend effective context length for language models and various methods, tasks and benchmarks exist to measure model’s effective memory length. However, through thorough investigations, we find limitations for currently existing evaluations on model’s memory. We provi…

2024

Hybrid Alignment Training for Large Language Models

ACL 2024findings

Alignment training is crucial for enabling large language models (LLMs) to cater to human intentions and preferences. It is typically performed based on two stages with different objectives: instruction-following alignment and human-preference alignment. However, aligning LLMs with these objectives…

2024

PartialFormer: Modeling Part Instead of Whole for Machine Translation

ACL 2024findings

The design choices in Transformer feed-forward neural networks have resulted in significant computational and parameter overhead. In this work, we emphasize the importance of hidden dimensions in designing lightweight FFNs, a factor often overlooked in previous architectures. Guided by this principl…

2024

Predictor-Corrector Enhanced Transformers with Exponential Moving Average Coefficient Learning

NeurIPS 2024poster

Residual networks, as discrete approximations of Ordinary Differential Equations (ODEs), have inspired significant advancements in neural network design, including multistep methods, high-order methods, and multi-particle dynamical systems. The precision of the solution to ODEs significantly affects…

Cited by 2SourcePDFScholar
2024

Revealing the Parallel Multilingual Learning within Large Language Models

EMNLP 2024main

Large language models (LLMs) can handle multilingual and cross-lingual text within a single input; however, previous works leveraging multilingualism in LLMs primarily focus on using English as the pivot language to enhance language understanding and reasoning. Given that multiple languages are a co…

2024

Scaling Laws Across Model Architectures: A Comparative Analysis of Dense and MoE Models in Large Language Models

EMNLP 2024main

The scaling of large language models (LLMs) is a critical research area for the efficiency and effectiveness of model training and deployment. Our work investigates the transferability and discrepancies of scaling laws between Dense Models and Mixture of Experts (MoE) models. Through a combination o…

Cited by 2SourcePDFScholar
2024

Soft Alignment of Modality Space for End-to-End Speech Translation

ICASSP 2024accepted

End-to-end Speech Translation (ST) aims to convert speech into target text within a unified model. The inherent differences between speech and text modalities often impede effective cross-modal and cross-lingual transfer. Existing methods typically employ hard alignment (H-Align) of individual speec…

Cited by 0SourceScholar
2023

Augmenting Large Language Model Translators via Translation Memories

ACL 2023findings

Using translation memories (TMs) as prompts is a promising approach to in-context learning of machine translation models. In this work, we take a step towards prompting large language models (LLMs) with TMs and making them better translators. We find that the ability of LLMs to “understand” prompts…

2023

Incorporating Probing Signals into Multimodal Machine Translation via Visual Question-Answering Pairs

EMNLP 2023long findings

This paper presents an in-depth study of multimodal machine translation (MMT), examining the prevailing understanding that MMT systems exhibit decreased sensitivity to visual information when text inputs are complete. Instead, we attribute this phenomenon to insufficient cross-modal interaction, rat…

Cited by 0SourcecodeScholar
2023

ManagerTower: Aggregating the Insights of Uni-Modal Experts for Vision-Language Representation Learning

ACL 2023long

Two-Tower Vision-Language (VL) models have shown promising improvements on various downstream VL tasks. Although the most advanced work improves performance by building bridges between encoders, it suffers from ineffective layer-by-layer utilization of uni-modal representations and cannot flexibly e…

2023

Rethinking and Improving Multi-task Learning for End-to-end Speech Translation

EMNLP 2023long main

Significant improvements in end-to-end speech translation (ST) have been achieved through the application of multi-task learning. However, the extent to which auxiliary tasks are highly consistent with the ST task, and how much this approach truly helps, have not been thoroughly studied. In this pap…

Cited by 0SourcecodeScholar
2023

TranSFormer: Slow-Fast Transformer for Machine Translation

ACL 2023findings

Learning multiscale Transformer models has been evidenced as a viable approach to augmenting machine translation systems. Prior research has primarily focused on treating subwords as basic units in developing such systems. However, the incorporation of fine-grained character-level features into mult…

Cited by 7SourcePDFScholar
2022

Learning Multiscale Transformer Models for Sequence Generation

ICML 2022spotlight

Multiscale feature hierarchies have been witnessed the success in the computer vision area. This further motivates researchers to design multiscale Transformer for natural language processing, mostly based on the self-attention mechanism. For example, restricting the receptive field across heads or…

2022

ODE Transformer: An Ordinary Differential Equation-Inspired Model for Sequence Generation

ACL 2022long

Residual networks are an Euler discretization of solutions to Ordinary Differential Equations (ODE). This paper explores a deeper relationship between Transformer and numerical ODE methods. We first show that a residual block of layers in Transformer can be described as a higher-order solution to OD…

2022

On Vision Features in Multimodal Machine Translation

ACL 2022long

Previous work on multimodal machine translation (MMT) has focused on the way of incorporating vision features into translation but little attention is on the quality of vision models. In this work, we investigate the impact of vision models on MMT. Given the fact that Transformer is becoming popular…

2021

Learning Light-Weight Translation Models from Deep Transformer

AAAI 2021technical

Recently, deep models have shown tremendous improvements in neural machine translation (NMT). However, systems of this kind are computationally expensive and memory intensive. In this paper, we take a natural step towards learning strong but light-weight NMT systems. We proposed a novel group-permut…

2021

Weight Distillation: Transferring the Knowledge in Neural Network Parameters

ACL 2021long

Knowledge distillation has been proven to be effective in model acceleration and compression. It transfers knowledge from a large neural network to a small one by using the large neural network predictions as targets of the small neural network. But this way ignores the knowledge inside the large ne…

Cited by 26SourcePDFScholar