There really is no problem with Alexa, per se.
The problem is in relying on Alexa to provide anything resembling an accurate account of who is visiting a website, and from where, when the website in question is associated with terrorist or other extremist movements.[1] Individuals who frequent such sites can reasonably be expected to have a higher-than-average concern about their privacy and security, since simple association with such movements is illegal in many countries, and even when not illegal, visiting such sites may be sufficient cause for various police and intelligence organizations to open an investigation.
What does this have to do with Alexa? Alexa is not spyware, but only because the user must voluntarily install the Alexa toolbar.[2] The following is from the FAQs at alexa.com [emphasis added]:
Question
How are Alexa's traffic rankings determined?Answer
Alexa's traffic rankings are based on the usage patterns of Alexa Toolbar users and data collected from other, diverse sources over a rolling 3 month period. A site's ranking is based on a combined measure of reach and pageviews. Reach is determined by the number of unique Alexa users who visit a site on a given day. Pageviews are the total number of Alexa user URL requests for a site. However, multiple requests for the same URL on the same day by the same user are counted as a single pageview. The site with the highest combination of users and pageviews is ranked #1.
If you are going to rely on data from Alexa in a study of people who are involved in extremist or other illegal activity, you have to provide a plausible explanation as to why your particular population would install the Alexa toolbar and thus compromise their own security.
Finally, I will tell you in no uncertain terms that Alexa's data for prominent al-Qaida websites does not resemble in the slightest the actual usage of those sites under direct observation.
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[1] See for example the otherwise excellent report Countering internet radicalisation in Southeast Asia, released by the Australian Strategic Policy Institute.
[2] Not all Alexa users will actually be volunteers. Computers at cyber cafes may have the toolbar installed, and in some parts of the world many people may be using computers where the operating system and core software, such as web browsers, were installed not from genuine or legitimate sources, but from system images that have been created and shared among users from a single source computer that had the Alexa toolbar installed.
Posted on 10 March 2009 @ 18:21