Diffusion auction is an emerging business model where a seller aims to incentivise buyers in a social network to diffuse the auction information thereby attracting potential buyers. We focus on designing mechanisms for multi-unit diffusion auctions. Despite several attempts at this problem, existing mechanisms are unsatisfactory in one way or another. Here, we propose two new mechanisms for multi-unit diffusion auction: (1) MUDAN which satisfies IC and a weakened form of efficiency, and (2) MUDAR which satisfies efficiency and a weakened form of IC. We define the mechanisms for the bottleneck case of the problem, namely when each buyer demands a single item, to which the more general multi-demand setting can be reduced. Our mechanisms are the first multi-unit diffusion auctions that satisfy a range of desirable properties that include truthfulness and efficiency conditions. This closes the gap left open by the previous work.

翻译：扩散拍卖是一种新兴商业模式，卖方旨在激励社交网络中的买家传播拍卖信息，从而吸引潜在买家。本文聚焦于多单元扩散拍卖的机制设计。尽管已有若干针对该问题的尝试，但现有机制或多或少存在不足。我们提出了两种新的多单元扩散拍卖机制：（1）MUDAN机制，满足激励相容性（IC）和一种削弱形式的效率；（2）MUDAR机制，满足效率和一种削弱形式的激励相容性。我们针对问题的瓶颈情形定义了机制，即每位买家仅需求单一物品，而更一般的多需求设定可归约至该情形。我们的机制是首批同时满足真实性及效率条件等多重理想属性的多单元扩散拍卖方案，从而弥合了前人工作遗留的理论空白。