Attention Oligopoly
将数字平台建模为注意力经纪人，它们掌握用户偏好信息并出售定向广告空间，研究平台集中度提高如何导致广告价格上涨、新进入者广告减少及消费者福利下降，并指出仅依赖平台总使用量的合并评估可能严重偏误。
We model digital platforms as attention brokers that have proprietary information about their users’ product preferences and sell targeted ad space to retail product industries. Retail producers—incumbents or entrants—compete for access to this attention bottleneck. We discuss when increased concentration among attention brokers results in a tightening of the attention bottleneck, leading to higher ad prices, fewer ads being sold to entrants, and lower consumer welfare in the product industries. The welfare effect is characterized in terms of patterns of individual usage across platforms. A merger assessment that relies on aggregate platform usage alone can be highly biased.