Wang et al. (2022) — ARXIV-2203.11171

Key takeaways

  • It is a decoding strategy, not a prompt. Chain-of-thought prompting is unchanged; what changes is that greedy decoding is replaced by sampling a diverse set of paths and marginalizing over them to the most consistent final answer. That makes it composable with anything else in this topic.
  • The intuition is that a hard problem admits many routes to one answer. Agreement between independently sampled derivations is evidence; a single greedy path has no such check, and is exposed to both local optimality and the stochasticity of one sample.
  • Gains across the board: GSM8K +17.9, SVAMP +11.0, AQuA +12.2, StrategyQA +6.4, ARC-challenge +3.9, over four model families at varying scale.
  • The cost is stated and bounded. More samples means more compute, and the authors’ own guidance is that five or ten recovers most of the gain because performance saturates quickly.
  • Two by-products the authors name. It supplies an uncertainty estimate and improves calibration, and it yields rationales worth collecting — the second of which is the seed of using it to generate fine-tuning data, which they flag as future work.

Standing in the anthology

The third document SOTA-279 named as uncovered. It is tagged inference-optimization as well as in-context-learning because it is literally a sampling algorithm, which that topic’s blurb names.

Its limitation is one the record already holds from a different direction: the authors note that models sometimes generate incorrect or nonsensical reasoning paths, and LIT-467’s own error analysis found correct answers reached through incorrect chains. Marginalizing over paths counts answers, not reasoning, so it improves the answer without making the trace trustworthy.