发表机构
Yale University; Google Research; Stanford University（耶鲁大学; 谷歌研究; 斯坦福大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究开创双边市场自动出价机制设计，证明无先验下效用诚实机制对LGFT有无界PoA，但提出在分布信息下实现激励相容、个体理性、预算平衡及最优流动性福利的双边机制，适用于匹配市场。
AI 中文摘要
自动出价已成为在线广告中的主导范式，它使广告主能够设定高层目标，而算法则负责实时出价优化。一个突出的例子是广告支出回报率（RoS）价值最大化器，它在满足总价值-花费约束的前提下最大化总价值。虽然大多数针对自动出价者的机制设计研究聚焦于单边市场，但许多现实平台涉及双边策略行为。我们开创了带有自动出价者的双边市场研究。首先，我们确立了一个严峻的负面结果：对于无先验环境下流动性交易收益（LGFT）这一具有挑战性的目标，一旦存在价值最大化代理，即使是在双向拍卖环境中，广泛的效用诚实、预算平衡机制类也具有无界的价格无政府状态（PoA）。随后，我们给出两个正面结果。在无先验的重复双向拍卖环境中，McAfee的贸易削减机制对LGFT具有无界PoA，但在RoS出价下对流动性福利实现了常数PoA，表明现成机制保留了有意义的福利保证。利用关于私人成本和价值的分布信息，我们设计了一个双边机制，该机制对每个代理在其相应目标下具有激励相容性、个体理性、事前弱预算平衡，并且只要市场至少一侧由RoS价值最大化者组成，就能实现最优流动性福利，即等价于最优LGFT。该结果适用于具有一般向下封闭可行性约束的匹配市场。这与Myerson-Satterthwaite不可能性定理形成鲜明对比，该定理排除了在双边交易中同时实现激励相容、个体理性和预算平衡时的最优效率，即使买方和卖方都是拟线性效用最大化者。
英文摘要
Autobidding has become a dominant paradigm in online advertising by enabling advertisers to set high-level goals while algorithms handle real-time bid optimization. A prominent example is the Return-on-Spend (RoS) value maximizer, which maximizes total value subject to an aggregate value-per-spend constraint. While most work on mechanism design for autobidders focuses on one-sided markets, many real-world platforms involve strategic behavior on both sides. We initiate the study of two-sided markets with autobidders. We first establish a stark negative result: for the challenging objective of liquid gains from trade (LGFT) in the prior-free setting, broad classes of utility-truthful, budget-balanced mechanisms have unbounded Price of Anarchy (PoA) once value-maximizing agents are present, even in double-auction environments. We then give two positive results. In the prior-free repeated double-auction setting, McAfee's Trade Reduction mechanism has unbounded PoA for LGFT but achieves constant PoA for liquid welfare under RoS bidding, showing that off-the-shelf mechanisms retain meaningful welfare guarantees. With distributional information regarding the private costs and values, we design a two-sided mechanism that is incentive compatible for each agent under its corresponding objective, individually rational, ex-ante weakly budget balanced, and achieves first-best liquid welfare, equivalently optimal LGFT, whenever at least one side of the market consists of RoS value maximizers. This result applies to matching markets with general downward-closed feasibility constraints. It contrasts sharply with the Myerson--Satterthwaite impossibility theorem~\citep{MS83}, which rules out first-best efficiency with incentive compatibility, individual rationality, and budget balance even in bilateral trade when both the buyer and the seller are quasi-linear utility maximizers.
CommentsTo appear in the 22nd Conference on Web and Internet Economics (WINE2026)
