π€ AI Summary
Existing large language modelβdriven social agents rely on static role definitions, limiting their ability to dynamically adapt to evolving interlocutors and contexts in non-stationary multi-turn dialogues. This work proposes the first online policy optimization framework tailored for social agents, formulating multi-turn social interaction as an adversarial multi-armed bandit problem. The action space combines fixed role descriptions with dynamic policy instructions, while a lightweight neural proxy predicts sparse rewards from interaction history, enabling continual adaptation without assuming environmental stationarity. Evaluated on the Sotopia benchmark, the proposed method significantly outperforms both static baselines and existing optimization strategies, demonstrating superior adaptability and robustness in complex social interactions.
π Abstract
Social simulation provides a compelling testbed for studying social intelligence, where agents interact through multi-turn dialogues under evolving contexts and strategically adapting opponents. Such environments are inherently non-stationary, requiring agents to dynamically adjust their strategies over time. However, most Large Language Model (LLM) based social agents rely on static personas, while existing approaches for enhancing social intelligence, such as offline reinforcement learning or external planners, are ill-suited to these settings, typically assuming stationarity and incurring substantial training overhead. To bridge this gap, we propose \textbf{ALSO} (\textbf{A}dversarial on\textbf{L}ine \textbf{S}trategy \textbf{O}ptimization), the first framework for online strategy optimization in multi-agent social simulation. ALSO advances social adaptation through two key contributions. (1) ALSO formulates multi-turn interaction as an adversarial bandit problem, where combinations of static personas and dynamic strategy instructions are treated as arms, providing a principled solution to non-stationarity without relying on environmental stability assumptions. (2) To predict rewards and generalize sparse feedback in multi-turn dialogues, ALSO introduces a lightweight neural surrogate to predict rewards from interaction histories, enabling sample-efficient exploration and continuous online adaptation. Experiments on the Sotopia benchmark demonstrate that ALSO consistently outperforms static baselines and existing optimization methods in dynamic environments, validating the effectiveness of adversarial online strategy optimization for building robust social agents.