Andon Labs
5 Arena runs is a small sample, so we ran 24 more runs in other business simulations (internal at Andon Labs): 12 runs with all-Fable 5 agents, and 12 with all-Opus 4.8. Fable 5 formed price-fixing cartels in 9 of 12 runs. Opus 4.8 only did it in 4 of 12.