Could removing Adsense from most pages enhance revenue?

A paradox for frustrated Adsense publishers

[numnum]

I'm revisiting a topic that's tossed around here from time to time. For simplicity's sake, let's assume you run a site that includes 100 pages, all of which contain the same Adsense units, page layout (CSS), and so forth. But your most-visited 20 pages account for 80% of your Adsense revenue (which is not atypical, I think). Now, if you remove Adsense from the remaining 80 pages, will your total revenue increase, decrease, or remain about the same (all else assumed unchanged)?

My guess is that earnings per impression would increase because (and this is also a guess about user behavior) a visitor is more likely to click on an ad while viewing the first page he/she visits than any subsequent page (all else equal). But would overall earnings increase?

What if you used a robots.txt file or tag to request that Google not index those 80 pages? Would that help, hinder, or have no effect on your overall earnings? (Assume that you have a useful internal linking structure that leads the user logically and easily around your site and to those other 80 pages.)

And if the answer to either or both questions is that your revenue would either increase or remain the same, what if you replace Adsense on those 80 pages with similarly positioned ads from another ad network, such as Adbrite? A free lunch?

I know, there are a host of factors that come into play here -- involving the Adsense bidding system, SEO, user behaviors, and so forth. Submit your analysis, and have fun.

[Leonard0]

Sally Stitts wrote a post about removing ads from poor performing pages back in July, 2009
[webmasterworld.com...]
Farmboy reported

I had a site of about 500 pages and about a year ago I removed AdSense from every page that was consistently getting a 1% or less AdSense CTR. Today, my AdSense earnings from the site are about the same as they were a year ago. I'm just earning that amount from less ads on the site.
I replaced the removed AdSense ads with another PPC program. The overall result is my income from the site has doubled in the past year.

Using DFP Small Business ad manager will let you set the minimum EPC for ads so that you don't have to check every page.

[Slashus]

If you just don't put any ads on those 80 pages - Googlebot might think that they are now magically better pages and rank them higher - generating more traffic to your site as a whole. Which would attract more traffic to your money pages.

[JCKline]

I keep my G ads to two ad blocks per page, not G's suggested 3 blocks + ad units. Three months ago I removed one ad of 2 ads on pages that don't generate much traffic. The earnings improved 25%.

[numnum]

That thread from 2009 is well worth reading. Thanks for the linking to it, Leonard10.

Let's assume hypothetically that all of your pages that include Adsense receive about the same number of page views per day (little deviation from the mean, suggesting easy site navigation and a logical taxonomy) and that for all of the pages the CTR is nearly the same as well (little deviation from the mean, suggesting a tightly focused site with useful content throughout). My hunch is that your total earnings would decline as either of these two measurements of deviation increases -- all else equal. So a big site with just a few really popular pages won't generate as much Adsense revenue as the same-sized site with many moderately popular pages. Google "smart prices" the latter site at a premium to the former. (Am I using the term "smart pricing" properly here?)

Starting right now, I'm trying an experiment with my site. I'm going to remove Adsense entirely from a group of pages that account for about 50% of all pages at my site but only about 5% of all page views. Fortunately, I've got a distinct set of SSIs for this group, so it's an easy task. (In fact, I'm already done.) The contextual ads shown on these pages tend to be tangential to the site's overall topic, and so the group's CTR is relatively low. Ironically, these are the pages that contain a lot of the meat that site users really want to find but have to drill down a few level to get to. Readers who drill down this far into my content are probably focused on the text and are probably ad-blind by this point. (Just a hunch on my part.)

The idea behind removing Adsense from these pages is to reward the persistent user with some ad-free content and to increase the site's overall Adsense CTR and eCPM. But will my total Adsense revenue hold, or possibly even increase?