In your opinion, Which methods do Google (and other PPC companies like Adbrite and CommissionJunction ) use to prevent click fraud ?? Thanks
I think they uses many factors. Such as IP addreses, Clicking time interval, Screen Resolution, Browser, Geo location, etc...
This thread is similar to what i have created few hours ago, from my experience ad network company both mobile and websites, like Admob, MobGold, Adsense, etc. They consider you fraud if your ads get click by robot, webcrawler, etc.
but IP address is variable and anyone can change it. A simple robot can click on the ads using different IP. So... How can they identify me ?
How do you do that ? Did you change the headers or using proxy server ? you could make a big money from MobGold, AdSense, Admob, etc.