Forum Moderators: martinibuster
I've just emailed them to request opt out. My epc is good at the moment, but my ctr is only middling.
I opted out and within a few days my drastically fallen ctr and eCPM shot back up along with earnings.
True. Though as ad clicks and earnings are counted in the normal stats, if 100% of your ads were site-targetted, you could have a very high CTR. And that is the experience on our site: with CPM Ads, CTR goes up and earnings go down.
>It is in Google's best interest to automatically serve only the best performing ads. I find it
>hard to belive that such a serious bug in the system would remain there unfixed for months
I think the problem is not having sufficient hard data to work on. Adsense Support recently helped us do some proper analysis on our site - taking us out of CPM Ads so that we could do a statistical comparison. This produced a 'statistically significant' result (using Mann Whitney, p<.05) showing that with CPM Ads disabled our CTR went down and Earnings per Visitor went up. But because the Adsense market is so complex, it still isn't possible to be certain that CPM Ads caused these changes. Nevertheless, Adsense have a copy of our report and have said that their engineers will look at the data.
It may be that CPM Ads only work for a particular type of site. However, if a site does get targetted, that ought to result in earnings going up. The fact that it doesn't (on our site) suggests that there may be a problem either in the algo or in knock-on effect on smartpricing.