A couple days ago on Carolina Middlebrook’s blog, she made a post entitled ‘Experiments to boost Adsense CTR‘. In this post she talks about removing ads from poorly performing sites, and go on to talk about smartpricing. While removing poorly performing sites will improve your overall CTR, I wouldn’t suggest removing ads from poorly performing sites. Instead, work on optimizing the ads. I’ve noticed that the CPC on my other sites shifts as other sites under my account gain traffic. Now, I don’t the reasoning behind this, but it works.
For example, I have a site that gets say xxx visitors a day, and converts with a 15% CTR, at an avg of $0.30 a click. Now, I get this PCP when I have that site going, along with an additional xxxxx impressions under my Adsense account. Now, I took off all the poorly performing websites, and over the next several weeks, the PCP went down to around $0.20. Because of this, I began to experiment with the number of impressions that my ads get under my Adsense account, and there was definitely a trend: the more impressions that were bad, the higher my PCP was on my 15% CTR website. As I said, I don’t see any reasoning behind this, but it does work, at least for the time being. Perhaps adding more poorly converting impressions makes the quality impressions look even higher quality.