Shuman Ghosemajumder, Google Business Product Manager for Trust & Safety, has once again slammed Click Forensics on their click fraud assessment by digging up all sorts of flaws in their study.
We found serious flaws in their counting of clicks – a more fundamental issue than their counting of click fraud. They were making basic counting mistakes and inflating the number of clicks by an average of 40%. The source of this problem is incorrectly counting page views – from users browsing through an advertiser's site – as clicks.
Shuman also explains the common flaw that occurs in click fraud companies when they wrongly count visits to PPC landing pages.
The assumption they're relying upon is that each visit to that URL corresponds to a unique click, and vice versa. But in practice this is not the case. Once a user visits that page, they often browse through the site, navigating through sub pages, and then return to the original landing page by hitting the back button. When the landing page is reloaded in the browser, it appears in the web log as though additional ad "clicks" are occurring.
In the month of December, Shuman claimed that Google AdWords Click Fraud is at or below 2%. Which implies that the actual number of click fraud is likely to be only a fraction of 1%. Contrary to this, click fraud agencies report that click fraud is actually 20% or so.