The Importance of Being Placed High
Position among ads has many effects.
Higher ads get more clicks.
Placing above a particular competitor is often important.
Higher ads have positive branding effect, even if they do not get clicked. [IAB study]
Is there a natural generalization of GSP that takes position constraints as input?
We study prefix constraints:
Advertiser i gives bid bi and position cutoff i
Ad i is never placed below position i