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Paper · Self-reward and self-play

When Can Self-Play Fix a False Belief? Answer Keys, Pass Bands and Replacement Rules in an Execution-Grounded Loop

An analysis of execution grounded self play reveals that training on self generated code execution only fixes a model's false beliefs if the answer key comes from an unplanted teacher model rather than the model's own flawed implementation.

When Can Self-Play Fix a False Belief? Answer Keys, Pass Bands and Replacement Rules in an Execution-Grounded Loop
Figure 1 of the paper, arXiv. Source
The loop

Qwen3 4B Base generates output prediction tasks and Python code, then executes the code to derive answer keys. The model trains on these self generated, execution verified keys to correct its own planted false beliefs about task specifications.

  1. Qwen3 generates tasks and code
  2. executes code for answer keys
  3. trains on verified keys
  4. corrects its own false beliefs
  1. Qwen3 generates tasks and code
  2. executes code for answer keys
  3. trains on verified keys
  4. corrects its own false beliefs
↻ The improved system does the next round, and the loop turns again.

Why it is a road to recursion

It demonstrates that execution grounded self play can correct a model's internal false beliefs, provided the verification signal escapes the model's own flawed implementation.

Evidence

A correct key from an unplanted teacher raised the truth rate from 0.03 to 0.58 after three rounds.

self playcode executionbelief correctionexpert iteration