Diffusion auction is a new model in auction design. It can incentivize the buyers who have already joined in the auction to further diffuse the sale information to others via social relations, whereby both the seller's revenue and the social welfare can be improved. Diffusion auctions are essentially non-typical multidimensional mechanism design problems and agents' social relations are complicatedly involved with their bids. In such auctions, incentive-compatibility (IC) means it is best for every agent to honestly report her valuation and fully diffuse the sale information to all her neighbors. Existing work identified some specific mechanisms for diffusion auctions, while a general theory characterizing all incentive-compatible diffusion auctions is still missing. In this work, we identify a sufficient and necessary condition for all dominant-strategy incentive-compatible (DSIC) diffusion auctions. We formulate the monotonic allocation policies in such multidimensional problems and show that any monotonic allocation policy can be implemented in a DSIC diffusion auction mechanism. Moreover, given any monotonic allocation policy, we obtain the optimal payment policy to maximize the seller's revenue.

中文翻译：

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激励兼容的扩散拍卖

扩散拍卖是拍卖设计的一种新模式。它可以激励已经加入拍卖的买家通过社会关系进一步将销售信息传播给其他人，从而提高卖家的收入和社会福利。扩散拍卖本质上是非典型的多维机制设计问题，代理人的社会关系与他们的投标复杂相关。在此类拍卖中，激励兼容性 (IC) 意味着每个代理商最好诚实地报告她的估价并将销售信息充分传播给她的所有邻居。现有工作确定了一些特定的扩散拍卖机制，而描述所有激励相容的扩散拍卖的一般理论仍然缺失。在这项工作中，我们确定了所有主导策略激励兼容（DSIC）扩散拍卖的充分必要条件。我们在此类多维问题中制定了单调分配政策，并表明任何单调分配政策都可以在 DSIC 扩散拍卖机制中实施。此外，给定任何单调分配策略，我们获得最优支付策略以最大化卖方的收入。