> switching to a model where ads are being paid for the time they're being displayed (pay X to have your ad appear here for Y time) the problem goes away
I don't think it does. How does the advertiser know what the spot on the site is worth without traffic estimates? See my response to chongli downthread: https://news.ycombinator.com/item?id=25431138
> Is it fraud if a real user "looks" at the ad but actually looks away from their screen? If they mute the sound? If they don't speak the language the ad is in?
None of these are fraud, because the ad is in front of a real user.
Fraud here doesn't mean "the ad doesn't perform as well as the advertiser hoped for some reason" it means "the ad was not actually shown to real users on the site, contrary to the agreement between the publisher and the advertiser".
I don't think it does. How does the advertiser know what the spot on the site is worth without traffic estimates? See my response to chongli downthread: https://news.ycombinator.com/item?id=25431138
> Is it fraud if a real user "looks" at the ad but actually looks away from their screen? If they mute the sound? If they don't speak the language the ad is in?
None of these are fraud, because the ad is in front of a real user.
Fraud here doesn't mean "the ad doesn't perform as well as the advertiser hoped for some reason" it means "the ad was not actually shown to real users on the site, contrary to the agreement between the publisher and the advertiser".