linear - 3:06 pm on Jul 19, 2005 (gmt 0)

I can't take credit for the idea, I think it was Trillianjedi who made the post I based my sceme on, but the improvement for me came in not showing the ads to registered forum users as often.

My current templates are set to show ads every time to guests (I get substantial SE referrals), and a 1 in 7 chance of an ad impression for registered users. I use a leaderboard centered above the posts/topics table on my post and topics pages respectively. I never show ads at the forum index or on obvious untargetable pages (who's online, etc.) I belnd my ads to the color sceme of the forum.

As far as how well it works, I can only say it seems to work better than continuously showing everybody ads. My CTR is lower than on content pages, but still good enough that I'm keeping the plan as is. FWIW, I think a 1% CTR on forums would thrill a lot of webmasters.

I think it works in another way as well--the additional imps that I am avoiding would otherwise drop my account-wide CTR. I am convinced there are certain CTR "breakpoints" that dictate (at least influence) what quality of ads you receive. In other words, I'm a lot happier when I keep my CTR above X%. Removing non-performing pages has helped, as has selective display of adsense units as described above. Your mileage may vary.