Why can't we just tell them which Stats entries are spam?This is, admittedly, such a simple suggestion - it surely must present part of the final solution.
If one considers the purposes behind referer spam, one can see a problem with having individual blog owners designate specific pageview entries, in their Stats logs, as referer spam.
There are actually multiple purposes for referer spam.
Look carefully at the entries, in your Stats logs. Are all of the websites, which are being advertised by non existent links to your blog, actually spammy? Chances are, if you look closely enough, you'll find one or two which just don't seem to fit the pattern.
- The volume of hits makes the pageview counts look suspicious.
- There's no link to your blog, from the websites.
- Looking closely at the content of the blog or website, it just does not look like the typical referer spam target.
This blog was honoured, as a false target, in October 2011. I have no doubt that other blogs and websites are also the targets of similar, deliberate attacks.
With referer spam used strategically, the spammers could simply adjust the volume of their attacks, to make innocent victims more visible, and more vulnerable to false accusation by the less observant blog owners, who simply want all referer spam stopped.
To guard against referer spam being used strategically, to attack innocent blogs and websites, any designations "This is referer spam!" would have to be complemented by "This is not referer spam!". Ultimately, all Stats pageview entries would have to be verified as "Spam!" or "Not spam!", to prevent referer spam from being successfully used as an attack technique. How many blog owners would want to scan their entire Stats log, daily, and mark all pageview entries as "Spam!" or "Not Spam!"?
Understanding the nature of referer spam, one sees that the only way to effectively combat it is to have Google globally examine all pageview activity for all blogs, over long periods of time, to identify actual referer spam - and to avoid falsely designating innocent third party blogs and websites as being intentional referer spam customers.