I saw this website showing demographic data about your website. http://www.quantcast.com/ How can this site knows the gender, age, race, salary, school data about people who visit your website? It also shows traffic. I doubt that this information is true. Just accessing your site traffic is one thing, but knowing information about who visits can only be an approximation. Did you test your site and what results did you get? You can check DP. What do you think? http://www.quantcast.com/forums.digitalpoint.com
It never made much sense to me - how on earth could they ever know someone's gender or race? Compete.com is referenced much more often in marketing articles than Quantcast is.
This is my personal ranking on these sites 1- Compete 2- Quancast 3- Alexa Based on accuracy of data, Alexa is actually the worst even thought it is the most well known and widely used.
Quantcast and Compete collects data from various publishers and they even buy data from ISPs. When people sign up with ISPs, they usually collect this kind of information, such as gender, location, age, etc. Having checked the stats for various websites, I would say their data is pretty inaccurate - often reporting alot less traffic. I guess it's better to understate traffic than overstating it.
They have a couple of papers about their methodology if you or anyone else wants to review it: http://www.quantcast.com/docs/display/info/Methodology *shrug* We pay attention to the data and suggest to our clients that they include their javascript in their site.
That makes sense to me for the ISP. In that case it is normal that it is inaccurate. An Internet account at an ISP can serve a family. For example: 1 man, 1 woman, 2 children. Just from that, you cannot really tell who is using Internet and who is not. I am wondering if ISPs are allowed to share this kind of information legally?