What happened?
OpenAI reported that process supervision significantly outperformed outcome supervision for training reward models on MATH solutions; its process-supervised model solved 78% of a representative held-out MATH subset, and the project released PRM800K with 800,000 step-level correctness labels.
Why it matters
Step-level verification became a durable component of later mathematical reasoning systems, providing training and selection signals that diagnose where a chain of reasoning first goes wrong rather than judging only its endpoint.
Significance rationale: The work made step-level human feedback a concrete and scalable research object for mathematical reasoning, directly comparing process and outcome supervision and releasing PRM800K as a large process-supervision dataset that influenced later verifier and reward-model work.
Evidence & status at a glance
- Significance
- H2 · Field milestone
- Verification
- Paper released
- Evidence level
- E3 · Inspectable artifact
- AI role
- Substantive AI support
- Formal assurance
- Artifact available
How should these labels be read? →
Contribution & verification
- Mathematical novelty
- Tooling only
- Interface
- Informal, Symbolic, Numeric
- AI contribution
- Language models generated mathematical solution trajectories and learned reward models scored intermediate reasoning steps; the correctness labels used for process supervision were supplied by human annotators.
- Human contribution
- Researchers designed the process-versus-outcome supervision comparison, data-collection and active-learning procedures, while human labelers supplied step-level judgments for PRM800K.
- Verification
- Paper released · E3 · Inspectable artifact · Artifact available
- Last reviewed
- 2026-09-11
Technical details
- Systems
- process-reward-model, prm800k
- Organizations
- openai
- Problems
- math-benchmark
- Methods
- process-supervision, process-reward-model, outcome-supervision, active-learning, verification
Verification history
- 2023-05-31 · Paper released · E2 · Research record
OpenAI released the research paper and official description comparing process and outcome supervision on MATH.
- 2023-05-31 · Paper released · E3 · Inspectable artifact
The public PRM800K repository exposes 800,000 step-level labels, labeling instructions, data splits and evaluation samples. E3 records inspectability and does not imply independent verification of the reported model results.
Corrections
No corrections recorded.