I think this is what Google detects about invalid clicks: - IP Address - Country - OS - Internet Browser - Cookies - System Specs (e.g. hard disk serial number, processor) - URL 'came from'
I think they have a spy camera behind everyones back! Seriously, what do you base these thoughts on? Or is this just a random guess?
There are a few other methods, but it comes down to detecting people who are stealing money from the people who pay for adwords. A blueprint of google's detection methods would only benefit those who are up to no good. I hope google takes more of these people to court and sues them for everything - as well as criminal charges.
OH Thanks . I always used to wonder that why don't they keep track of MAC instead of IP's and now I just rememberd the networking concept that routers(i.e. layer 3 device) do not pass mac addresses. They keep there routing tables with only IP in them, that is why we can only get IP geez, you learn new things everyday.