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20112026
most citedDirect Preference Optimization: Your Language Model is Secretly a Reward Model

294 citations · 570 across the 29 of their papers we have counts for

collaborators

30 papers

cs.LG2026

Reliable and Responsible Foundation Models: A Comprehensive Survey

Xinyu Yang, Junlin Han, Rishi Bommasani +49

Foundation models, including Large Language Models (LLMs), Multimodal Large Language Models (MLLMs), Image Generative Models (i.e, Text-to-Image Models and Image-Editing Models), a…

cs.AI2025★ 1 cited

Just Enough Thinking: Efficient Reasoning with Adaptive Length Penalties Reinforcement Learning

Violet Xiang, Chase Blagden, Rafael Rafailov +4

Large reasoning models (LRMs) achieve higher performance on challenging reasoning tasks by generating more tokens at inference time, but this verbosity often wastes computation on…

cs.LG2025

Big-Math: A Large-Scale, High-Quality Math Dataset for Reinforcement Learning in Language Models

Alon Albalak, Duy Phung, Nathan Lile +8

Increasing interest in reasoning models has led math to become a prominent testing ground for algorithmic and methodological improvements. However, existing open math datasets eith…

cs.CV2025

MJ-VIDEO: Fine-Grained Benchmarking and Rewarding Video Preferences in Video Generation

Haibo Tong, Zhaoyang Wang, Zhaorun Chen +11

Recent advancements in video generation have significantly improved the ability to synthesize videos from text instructions. However, existing models still struggle with key challe…

cs.AI2025★ 2 cited

Towards System 2 Reasoning in LLMs: Learning How to Think With Meta Chain-of-Thought

Violet Xiang, Charlie Snell, Kanishk Gandhi +11

We propose a novel framework, Meta Chain-of-Thought (Meta-CoT), which extends traditional Chain-of-Thought (CoT) by explicitly modeling the underlying reasoning required to arrive…

cs.LG2024★ 2 cited

D5RL: Diverse Datasets for Data-Driven Deep Reinforcement Learning

Rafael Rafailov, Kyle Hatch, Anikait Singh +9

Offline reinforcement learning algorithms hold the promise of enabling data-driven RL methods that do not require costly or dangerous real-world exploration and benefit from large…

cs.AI2024★ 7 cited

Agent Q: Advanced Reasoning and Learning for Autonomous AI Agents

Pranav Putta, Edmund Mills, Naman Garg +4

Large Language Models (LLMs) have shown remarkable capabilities in natural language tasks requiring complex reasoning, yet their application in agentic, multi-step reasoning within…

cs.CL2024

PERSONA: A Reproducible Testbed for Pluralistic Alignment

Louis Castricato, Nathan Lile, Rafael Rafailov +2

The rapid advancement of language models (LMs) necessitates robust alignment with diverse user values. However, current preference optimization approaches often fail to capture the…

cs.CV2024

MJ-Bench: Is Your Multimodal Reward Model Really a Good Judge for Text-to-Image Generation?

Zhaorun Chen, Yichao Du, Zichen Wen +16

While text-to-image models like DALLE-3 and Stable Diffusion are rapidly proliferating, they often encounter challenges such as hallucination, bias, and the production of unsafe, l…

cs.LG2024★ 4 cited

Preference Fine-Tuning of LLMs Should Leverage Suboptimal, On-Policy Data

Fahim Tajwar, Anikait Singh, Archit Sharma +6

Learning from preference labels plays a crucial role in fine-tuning large language models. There are several distinct approaches for preference fine-tuning, including supervised le…

cs.RO2024★ 43 cited

OpenVLA: An Open-Source Vision-Language-Action Model

Moo Jin Kim, Karl Pertsch, Siddharth Karamcheti +15

Large policies pretrained on a combination of Internet-scale vision-language data and diverse robot demonstrations have the potential to change how we teach robots new skills: rath…

cs.CL2024★ 1 cited

Self-Supervised Alignment with Mutual Information: Learning to Follow Principles without Preference Labels

Jan-Philipp Fränken, Eric Zelikman, Rafael Rafailov +3

When prompting a language model (LM), users often expect the model to adhere to a set of behavioral principles across diverse tasks, such as producing insightful content while avoi…

cs.CL2024★ 1 cited

Disentangling Length from Quality in Direct Preference Optimization

Ryan Park, Rafael Rafailov, Stefano Ermon +1

Reinforcement Learning from Human Feedback (RLHF) has been a crucial component in the recent success of Large Language Models. However, RLHF is know to exploit biases in human pref…

cs.LG2024★ 2 cited

Aligning Modalities in Vision Large Language Models via Preference Fine-tuning

Yiyang Zhou, Chenhang Cui, Rafael Rafailov +2

Instruction-following Vision Large Language Models (VLLMs) have achieved significant progress recently on a variety of tasks. These approaches merge strong pre-trained vision model…

cs.LG2024★ 1 cited

MOTO: Offline Pre-training to Online Fine-tuning for Model-based Robot Learning

Rafael Rafailov, Kyle Hatch, Victor Kolev +3

We study the problem of offline pre-training and online fine-tuning for reinforcement learning from high-dimensional observations in the context of realistic robot tasks. Recent of…

cs.CV2023★ 4 cited

Diffusion Model Alignment Using Direct Preference Optimization

Bram Wallace, Meihua Dang, Rafael Rafailov +7

Large language models (LLMs) are fine-tuned using human comparison data with Reinforcement Learning from Human Feedback (RLHF) methods to make them better aligned with users' prefe…

cs.CL2023★ 3 cited

An Emulator for Fine-Tuning Large Language Models using Small Language Models

Eric Mitchell, Rafael Rafailov, Archit Sharma +2

Widely used language models (LMs) are typically built by scaling up a two-stage training pipeline: a pre-training stage that uses a very large, diverse dataset of text and a fine-t…

cs.LG2023★ 1 cited

Offline Retraining for Online RL: Decoupled Policy Learning to Mitigate Exploration Bias

Max Sobol Mark, Archit Sharma, Fahim Tajwar +3

It is desirable for policies to optimistically explore new states and behaviors during online reinforcement learning (RL) or fine-tuning, especially when prior offline data does no…

cs.LG2023★ 2 cited

Contrastive Preference Learning: Learning from Human Feedback without RL

Joey Hejna, Rafael Rafailov, Harshit Sikchi +4

Reinforcement Learning from Human Feedback (RLHF) has emerged as a popular paradigm for aligning models with human intent. Typically RLHF algorithms operate in two phases: first, u…

cs.RO2023★ 103 cited

Open X-Embodiment: Robotic Learning Datasets and RT-X Models

Embodiment Collaboration, Abby O'Neill, Abdul Rehman +291

Large, high-capacity models trained on diverse datasets have shown remarkable successes on efficiently tackling downstream applications. In domains from NLP to Computer Vision, thi…

cs.LG2023

Contrastive Example-Based Control

Kyle Hatch, Benjamin Eysenbach, Rafael Rafailov +4

While many real-world problems that might benefit from reinforcement learning, these problems rarely fit into the MDP mold: interacting with the environment is often expensive and…

cs.LG2023★ 294 cited

Direct Preference Optimization: Your Language Model is Secretly a Reward Model

Rafael Rafailov, Archit Sharma, Eric Mitchell +3

While large-scale unsupervised language models (LMs) learn broad world knowledge and some reasoning skills, achieving precise control of their behavior is difficult due to the comp…

cs.CL2023★ 5 cited

Just Ask for Calibration: Strategies for Eliciting Calibrated Confidence Scores from Language Models Fine-Tuned with Human Feedback

Katherine Tian, Eric Mitchell, Allan Zhou +5

A trustworthy real-world prediction system should produce well-calibrated confidence scores; that is, its confidence in an answer should be indicative of the likelihood that the an…

cs.RO2022★ 10 cited

Vision-Based Manipulators Need to Also See from Their Hands

Kyle Hsu, Moo Jin Kim, Rafael Rafailov +2

We study how the choice of visual perspective affects learning and generalization in the context of physical manipulation from raw sensor observations. Compared with the more commo…