hi i can only quot the best in the filed so here it comes:

mat cuts:
"That whooshing sound you hear is all the SEOs going to install the Compete Toolbar. Compete claims 2 million users help it compute metrics, and I’d be very surprised if all those participants were toolbar users. Yep, digging through the FAQ, they mention “ISP relationships,” which presumably means that they’re buying user data from ISPs. ISP relationships can be a huge source of metrics bias. For example, some ISPs partner with Yahoo, and users on those ISPs are probably more likely to visit Yahoo. Other ISPs partner with Google. And savvy users that use smaller providers such as Covad or Speakeasy are likely not counted at all.

Because you don’t know which ISPs are selling user data to companies such as Compete or Hitwise, you don’t know what biases are baked into those companies’ metrics–and the metrics companies won’t tell you. Maybe I’m cynical about metrics lately, but Rand Fishkin looked into this recently. He got data from 25 blogs (including mine) and then compared that data with a bunch of metrics services (including Compete). His conclusion? “Based on the evidence we’ve gathered here, it’s safe to say that no external metric, traffic prediction service or ranking system available on the web today provides any accuracy when compared with real numbers. … The sad conclusion is that right now, no publicly available competitive analysis tool we’re aware of provides solid value.” Go read his post–it’s a good one."

you can find his thoughts about alexa stats  here

a-word-about-metrics-part-ii

hope you found this illuminating... 

tzvika avnery

search engine optimization

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