The Illusion of Rationality: Tacit Bias and Strategic Dominance in Frontier LLM Negotiation Games

Summary

Researchers revisited the NegotiationArena framework and ran controlled simulations of frontier LLMs across three multiturn bargaining games: buyer-seller, multiturn ultimatum, and resource exchange. Models diverged into model-specific strategic equilibria rather than converging, showed persistent numerical and semantic anchoring where initial offers predicted final agreements, and some models systematically achieved higher payoffs than others.