Process Reward Models: How Step-by-Step Supervision and Search Drive LLM Reasoning
When large language models tackle complex multi-step reasoning (such as formal mathematics, algorithm synthesis, or multi-hop logic), evaluating only the final answer creates a severe credit assignment bottleneck. An outcome-based verifier can confirm whether a final numerical result is correct, but it cannot determine whether the underlying derivation was logically sound or reached the right answer through compounding hallucinations and lucky cancellations. Process Reward Models (PRMs) resolve
1 min