Does low CTR really equal low EPC?

or is this a webmaster's myth?

[annej]

There are two threads going right now that seem to assume that it's best to take all AdSense units off that have low CTR. Actually this theory has been going on since smart pricing began.

In the AdSense help section, "Maximize ad space with multiple ad units", we are encouraged to use more ads in pages with text that requires the visitor to scroll down and forums with long threads on one page. Does that mean AdSense is tricking us into lowering our EPC by telling us to do this?

It just doesn't make sense to me. It seems to me that units with fewer clicks may bring more serious customers to advertisers. For example if someone reads all of an article then clicks on an ad that interests him or her it seems like that person would be more serious about the ad then someone who just glances at the page then clicks on an ad to move on. Even with forums that are usually low CTR if seems to me if a regular visitor clicks on an ad they probably saw an ad for a product that they are sincerely interested in.

Maybe my assumptions are wrong but I don't see why low CTR would mean low EPC. I'm willing to look at the other side though if there are some compelling arguments.

[ronburk]

Low ROI = Low EPC (eventually... if Google can detect the ROI...)
Low CTR sometimes = Low ROI

People who detect the "sometimes" case leap to the conclusion that there's a causal connection going all the way from low CTR to low EPC.

[david_uk]

In my case, I tended to see less relevant ads in the other blocks. Maybe that was a contributory factor to the fact that the ctr in other units was very poor.

It was my experience that dumping the second block increased the ctr. If the subsequent increase in epc wasn't as a result of smartpricing, then I can't suggest why it happened.

[hunderdown]

You have to test to see what holds for your site. There certainly could be circumstances in which CTR has no impact on EPC. But I've experienced a rise in EPC associated with taking ads off pages where I (almost) never got clicks (one adblock per page), and others have found a benefit in removing extra ad blocks on two- or three-adblock pages. As ronburk points out, there may not be a direct relationship in the algorithm. But CTR, at least within certain ranges, seems to be associated with something that in turn is associated with smart pricing's impact on EPC.

Very nebulous, of course, so you really have to see what works for you--which may run counter to the advice AdSense gives, which is one size fits all its approach.

[annej]

I'm in the process of dropping my bottom ads to see what will happen in my case.

Am I correct in understanding that smart pricing is set by account not by site or page? I have some minor sites that don't get very good CTR and and wondered if I should drop the ads from them as well to make the experiment complete.