Google has just published it's latest guidelines on increasing cost per click
The dos and donts to increase cost per click - Inside AdSense
Upon reading this I realised that I disagreed with several of the points, but in fact I actually disagree with the whole premise.
I'm not actually interested in increasing cost per click, I'm interested in increasing revenue which is clicks x cpc. The issue in focusing in increasing cpc is that it assumes that at least one person is clicking on the adverts. I'm also interested in keeping my readers.
"Enable all of your ad units to show both text and image/rich media ads. By increasing the number of advertisers competing for your ad units, the ad auction will make sure that the highest paying ad will be shown"
My blogs are focused, one is about animation, one is about flea circuses and one is about model engineering. For example if someone like Sony, Nike or Cocacola are doing a massive promtion then they will pay lots for adverts regardless of where they are. So their cost per click will be high. However the people on my sites are not there to buy shoes, they are there to read about animation so they might not click on the adverts, even if they later go out and buy shoes from a shoe shop. If however I had an advert about animation software, microscopes or machine tools then they'd happily click on the adverts and hopefully also end up buying a product that they were interested in.
"Keep your filter list small so you don’t lower your revenue potential by blocking the highest-paying ads"
So if the highest bidder is say a pharmacutical company selling blue triangular pills then I'd have those on my site. One reader might click on the advert and I might get loads for that click. However all of the other 300 or so readers who are not interested in blue triangles might be put off and stop reading the blog all together. This is not a problem for google or for the advertisers as there are plenty of other sites that have their adverts on, it is a problem for me as I've just lost a load of readers. I've actually got the complete opposite, I've a very restrictive list, I looked at the percentage ad impressions and the % earlings. For example at the moment "health" has a 0.9% impressions and 0.0% earnings, so that's nearly 1% adverts effectively wasted. "Gardening" on the other hand has 11.8% of impressions and 13.6% of earnings so if I blocked those health adverts then my revenue could potentially increase by just over 1%.
"Increase the number of ads competing for your site by setting up your custom channels for placement targeting"
This I do agree with, you should clearly describe your custom channel, mine are currently
"Reports about the animation industry and animated films, including stop motion, cgi and traditional techniques."
"A look into the microscopic world of educated, industrious and trained fleas. Covering history, current performances, anything minature and cultural references to flea circuses. Also includes general news on fleas such as National Flea Week"
"Setting up and using a small shed as a model engineering workshop. Projects covered include metal work, machining (with lathe tools), casting and DIY."
With these I hope to target relavent advertisers who will enhance my blog with their adverts and hence keep themselves and my readers happy. In return I expect more clicks and hence more advertising revenue rather than just high CPC.