Sustaining a Good Impression: Mechanisms for Selling Partitioned Impressions at Ad Exchanges
Authors: Mehta, Sameer; Dawande, Milind; Janakiraman, Ganesh; Mookerjee, Vijay
Journal: Information Systems Research (2020)
<jats:p> At an ad exchange, impressions are sold to advertisers in real time through an auction mechanism. The traditional mechanism at these exchanges selects a single advertiser whose ad is displayed over the entire duration of an impression, that is, throughout the user's visit. We argue that such a mechanism leads to an allocative inefficiency. Our goal in this paper is to address this efficiency loss by offering mechanisms in which multiple ads can be displayed sequentially over the lifetime of the impression. We consider two plausible settings—one where each auction is individually rational for the advertisers and another where advertisers are better off relative to the traditional mechanism over the long run—and derive an optimal mechanism for each setting. Under the former mechanism, whereas the ad exchange always benefits relative to the traditional mechanism, the advertisers can either gain or lose—we demonstrate both these possibilities. The optimal mechanism for the latter setting is a mutually beneficial mechanism in that it guarantees a win–win for both the parties relative to the traditional mechanism over the long run. Happily, for both the mechanisms, the allocati…