Short history
Alexa Internet, Inc. is a California-based subsidiary company of Amazon.com that is known for its toolbar and website. Once installed, the toolbar collects data on browsing behavior which is transmitted to the website where it is stored and analyzed and is the basis for the company's web traffic reporting.
Source:
http://en.wikipedia.org/wiki/Alexa_Internet
'How' it works
The company offered a toolbar that gave Internet users suggestions on where to go next, based on the traffic patterns of its user community. Alexa also offered context for each site visited: to whom it was registered, how many pages it had, how many other sites pointed to it, and how frequently it was updated.
[4]
Alexa ranks sites based on tracking information of users of its
Alexa Toolbar for
Internet Explorer and from integrated sidebars in
Firefox and
Chrome.
[15] [16] Hence the page is only ranked between users who have these sidebars installed and may be biased if specific audience is reluctant to do this (
Windows Defender has classified the sidebar as malware while it assigns it to
trojans where it does not belong
[17]). Also, the rank is based on three month data
[18] and takes a long time to reflect changes in content that may happen after the domain has been sold
[citation needed]. Finally low ranks cannot be accurate not just because of the lack of data but also because of statistic laws related to the
long tail distribution. The same laws make ranking of the popular sites highly accurate.
[19]
Source:
http://en.wikipedia.org/wiki/Alexa_Internet
Why it 'works' for Iranians
Characterization of (national) web it outputs
Shared:
Amongst the URLs that were common across 5 platforms (including Alexa), there was a mix of news, entertainment, and sport websites. Most of the news websites were based in Iran, meaning that they are in some way controlled by the government as they have to abide my the rules and regulations of the Islamic State in order not to be shut down. Except for Facebook and BBC.co.uk (which was probably being used as a way into BBC Persian), and two basic file sharing sites, all of the websites were in Persian. Only one blog was common across the lists (including Alexa), which was a general blog about science, technology and the arts.
Unique:
The unique URLs for Alexa were quite diverse, including many music and file sharing websites. Blogs did not feature strongly at all.
site locations
TOP 500 Iranian website, Alexa.com
language it outputs
audience
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