TheMadScientist - 11:53 pm on Nov 29, 2012 (gmt 0)

And if you think that 1k zombies per day doesn’t influence on your bounce signal/ user experience why don’t visit the blackhat world and find some1 who can send you some visits to mess with your bounce and user experience rating... doesn’t harm or?

Google doesn't have access to your server logs or visitor data, so having a black-hat send you some 'zombie visitors' that puts a visit in your logs with Google as the referrer doesn't harm anything WRT rankings, and again, Google has said for years bounce rate is a noisy signal they either don't use or only use with little impact on rankings.

Click-thru, click-back, re-click (a subset of bounce rate) is more reliable and could be used, but even if you could find a black-hat with a bot advanced enough to parse the AJAX Google uses now and trick their system into thinking there was a real query and click and click back to the results and another click or query, when there wasn't so the 'chain of events' was tracked by Google (not likely, but the only way they would know it happened) there would be a definite pattern to the clicks, timing, site/page(s) clicked, query (or queries), etc. tracked and it would, very likely (most certainly), be discounted (or removed) from ranking impact, because Google doesn't like to have their results manipulated and something like you're talking about would be very obvious behavior in a large dataset (it's as easy as for them to see an 'odd pattern' in their data as it is for you in your stats, so there's no way what you're talking about would go unnotice as 'manipulative' and 'thrown out' or 'severely discounted' by their system), especially when they have access to things like toolbar data that would show a distinctly different pattern from real visitors.

Also, assuming, they're real people who 'just don't buy', you cannot tell what's happening on other sites (pages) on the same page of the SERPs for the same queries at the same time as yours, so a click-thru, click-back, re-click from a real visitor who doesn't purchase really doesn't tell you anything, because you don't know how many sites (results) the visitor is doing the same thing on, so there's no way of knowing if it has an influence on your rankings, but I don't see people reporting total loss in rankings when they report zombie traffic, so unless someone has definitive proof otherwise, it does not seem overall ranking impact from zombie traffic is at all likely.

ADDED: Third, if there's really an impact, the 'traffic drop' from zombie traffic should not be a 'one-time-event', but rather an on-going slide, eventually to nothing, because the zombie traffic is an on-going event, which means someone like Backdraft7 who has been seeing an odd traffic pattern for years should be totally out of the rankings or very close by now, but that's not the case.

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