位置拍卖与平台企业价格歧视

Position Auction and Price Discrimination of Platform Enterprise

位置拍卖是否可以作为一种有效的机制,使得电商平台上不同类型的商户显露其真实类型,进而为平台实行价格歧视提供可能?笔者研究发现:当电商平台上存在高档次高质量(θ_H)商户、低档次高质量(θ_(L1))商户和低档次低质量(θ_(L2))商户时,虽然不同类型的商户在位置拍卖中的最优竞标价有着确定的关系,但平台企业仅通过位置拍卖所产生的最优竞标价格难以达到更加精确筛选商户类型的目的;当平台企业设定满足一定条件的歧视性平台接入费时,商户为了自身利润最大会按照自身的最优竞标价格进行投标,从而产生了分离均衡。本研究还证明了任何导致分离均衡的歧视性平台接入费连同三类商户的最优竞标价格组成了所提出的局部无妒忌均衡,说明平台上的商户之间达到了一个比较稳定的均衡状态;而且当满足一些条件的时候(如商户θ_(L1)和商户θ_(L2)之间的质量差很小时),平台企业在分离均衡和局部无妒忌均衡的条件下所获得的最大利润与理论最大利润会非常接近。

The paper studies that whether position auction is an effective way to distinguish the merchant＇s real type,and whether platform enterprise can execute the price discrimination. The research finds that when there are three types of merchants that are of high level and good quality,low level and good quality and low level and bad quality,different types of merchants have some confirmed connections on position auction. But platform enterprise can hardly distinguish the merchants＇ type by the best bidding prices. When the platform enterprise sets a discrimination usage fee for a merchant that satisfied specific conditions,the merchant will bid to maximize her profit,so it will reach a separating equilibrium. In addition,the research also confirms that companying with the optimized bidding prices of three types of merchants,platform discrimination usage fee which results in the separating equilibrium leads to locally envy-free equilibrium. And the conclusion indicates the equilibrium is stable among different types of merchants. When some conditions are satisfied,the maximum profits gained by platform enterprises will approximate the theoretical profits in the condition of separating equilibrium and locally envy-free equilibrium.