We consider a multi-agent delegated search without money, which is the first to study the multi-agent extension of Kleinberg and Kleinberg (EC'18). In our model, given a set of agents, each agent samples a fixed number of solutions, and privately sends a signal, e.g., a subset of solutions, to the principal. Then, the principal selects a final solution based on the agents' signals. Our model captures a variety of real-world scenarios, spanning classical economical applications to modern intelligent system. In stark contrast to single-agent setting by Kleinberg and Kleinberg (EC'18) with an approximate Bayesian mechanism, we show that there exist efficient approximate prior-independent mechanisms with both information and performance gain, thanks to the competitive tension between the agents. Interestingly, however, the amount of such a compelling power significantly varies with respect to the information available to the agents, and the degree of correlation between the principal's and the agent's utility. Technically, we conduct a comprehensive study on the multi-agent delegated search problem and derive several results on the approximation factors of Bayesian/prior-independent mechanisms in complete/incomplete information settings. As a special case of independent interest, we obtain comparative statics regarding the number of agents which implies the dominance of the multi-agent setting ($n \ge 2$) over the single-agent setting ($n=1$) in terms of the principal's utility. We further extend our problem by considering an examination cost of the mechanism and derive some analogous results in the complete information setting.
翻译:我们研究无货币的多智能体委托搜索问题,这是首次对Kleinberg和Kleinberg (EC'18) 的多智能体扩展进行探索。在我们的模型中,给定一组智能体,每个智能体采样固定数量的解,并私下向委托方发送信号(例如,解的某个子集)。随后,委托方根据智能体的信号选择最终解。该模型涵盖了从经典经济学应用到现代智能系统的多种现实场景。与Kleinberg和Kleinberg (EC'18) 在单智能体设置中采用近似贝叶斯机制形成鲜明对比,我们证明,由于智能体间的竞争张力,存在高效的近似先验无关机制,能够同时带来信息增益和性能提升。然而有趣的是,这种竞争力量的大小显著依赖于智能体可获得的信息量,以及委托方与智能体效用之间的相关程度。在技术层面,我们对多智能体委托搜索问题进行了全面研究,推导出关于完全信息/不完全信息环境下贝叶斯/先验无关机制近似比的若干结果。作为独立感兴趣的特例,我们获得了关于智能体数量的比较静态分析,结果表明多智能体设置(n≥2)在委托方效用方面优于单智能体设置(n=1)。我们还进一步考虑了机制的检验成本,在完全信息设定下得到了类似的结果。