AI Post-Training Research

We work on frontier challenges in AI post-training with an open science approach

Latest post-training research news

Discover our latest AI publications and updates from the research lab

Meta Chain-of-Thought: Unlocking System 2 Reasoning in LLMs

Meta Chain-of-Thought: Unlocking System 2 Reasoning in LLMs

While current language models excel at pattern recognition, they often struggle with tasks requiring genuine reasoning—the kind of multi-step, logical deduction that humans use to solve complex problems. Our research addresses this fundamental gap by developing models that learn how to think through problems, rather than merely memorizing solutions. We introduce novel approaches combining tree search algorithms, process guidance through reward models, and meta-learning frameworks to enable more robust reasoning capabilities. Our work spans mathematical proof generation, scientific problem-solving, and complex decision-making tasks, with the goal of advancing AI systems beyond pattern matching toward true analytical thinking.

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GenRM: Generative Reward Models for AI Alignment

GenRM: Generative Reward Models for AI Alignment

We introduce Generative Reward Models (GenRM), a novel approach to AI alignment that combines the strengths of human feedback and AI-generated feedback. Our research focuses on improving AI systems' ability to understand and adhere to human values and preferences across diverse contexts. By leveraging Chain-of-Thought (CoT) reasoning and innovative training techniques, GenRM aims to create more robust, generalizable, and ethically aligned AI systems.

RLHF and RLAIF in GPT-NeoX

RLHF and RLAIF in GPT-NeoX

SynthLabs and EleutherAI are excited to announce large scale post training and preference learning in GPT-NeoX, one of the most widespread and adopted pretraining frameworks for large scale language models. One of the many efforts within our deep partnership with EleutherAI is to improve the accessibility and performance of preference learning at scale.

PERSONA: A Reproducible Testbed for Pluralistic Alignment

PERSONA: A Reproducible Testbed for Pluralistic Alignment

PERSONA introduces a reproducible testbed designed to evaluate and improve LLM pluralistic alignment through 1,586 synthetic personas derived from US census data. The framework encompasses 3,868 prompts and 317,200 feedback pairs, establishing both PERSONA Bench for systematic evaluation of language models' role-playing capabilities and a comprehensive dataset for developing future alignment benchmarks.

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Research Team

Rafael Mitkov Rafailov

Rafael Mitkov Rafailov

Research Scientist

Selected Work

Alon Albalak

Alon Albalak

Research Scientist

Selected Work

Collaborators

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Recent Publications

Our most recent 5 publications

5 publications

2025-01-07

Meta Chain-of-Thought: Unlocking System 2 Reasoning in LLMs

Dakota Mahan, Duy Van Phung, Rafael Rafailov, Chase Blagden, Nathan Lile, Louis Castricato, Jan-Philipp Fränken, Chelsea Finn, Alon Albalak

2024-10-3

GenRM: Generative Reward Models for AI Alignment

Dakota Mahan, Duy Van Phung, Rafael Rafailov, Chase Blagden, Nathan Lile, Louis Castricato, Jan-Philipp Fränken, Chelsea Finn, Alon Albalak

2024-10-09

RLHF and RLAIF in GPT-NeoX

Dakota Mahan, Quentin Anthony, Louis Castricato, Nathan Lile, Stella Biderman

2024-07-24

PERSONA: A Reproducible Testbed for Pluralistic Alignment

Louis Castricato, Nathan Lile, Rafael Rafailov, Jan-Philipp Fränken, Chelsea Finn

2024-02-12

Suppressing pink elephants with direct principle feedback

Louis Castricato, Nathan Lile, Suraj Anand, Hailey Schoelkopf, Siddharth Verma, Stella Biderman


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