Does the prompt-only imitation game settle or cycle, and does beating the latest detector mean beating the others?
research/mimic-crossplay
Does the prompt-only imitation game settle or cycle? Every imitator prompt from mimic-loop against every detector prompt (0.5B on both sides): pure equilibria below chance (reddit 0.396, reviews 0.292), no cycles at a noise margin, and text length tracks detector accuracy. Stylised, one loop seed; model-size question open.
What it found
Follow-up to mimic-loop. Every imitator prompt any of its eight runs produced is scored against every detector prompt (Qwen2.5-0.5B-Instruct on both sides, 48 titles per cell, detector paired accuracy, 0.50 = chance), giving a 10×7 matrix on reddit and 9×10 on reviews. Both zero-sum games have a pure equilibrium with value below chance (reddit 0.396, 95% title-bootstrap 0.28 to 0.47; reviews 0.292, 0.17 to 0.34): no detector prompt guarantees chance, and no cell exceeds 0.56. On reviews the unadapted plain imitator prompt is the equilibrium imitator. Mean text length correlates with detector accuracy (Spearman 0.76 on reddit, 0.30 on reviews). No cycles at a 0.15 noise margin; overfitting to the latest opponent is small and not established. Stylised: one loop seed, a 0.5B detector that starts below chance. The model-size question is left open.
A figure from its own output
Paper, code and results
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Produced with AI assistance (Claude). Results are from the code in this repository and are simulated or stylised unless the abstract says otherwise; nothing here implies affiliation with or endorsement by any lab, researcher or company cited. MIT licensed.