Disadvantages of Alexa
Although there are several advantages to Alexa’s toolbar, it is also accompanied with
certain constraints. It is important to note that, in our view, the toolbar’s advantages outweigh its
disadvantages and hence makes B-COP a practical model that many managers can use.
First, Alexa has some technical limitations since it uses toolbar technology. It only works
with Internet Explorer and Windows operating systems. Notably, the Alexa toolbar does not
work for those who might use the AOL browser or any of the Netscape browsers (including
Mozilla Firefox). Second, since Amazon owns Alexa.com, the data may over-represent the
prominence of Amazon.com. Third, Alexa is not able to distinguish between sub-domains and
sub-pages from its parent domains, it only provides rankings for top-level rankings. For
example, Alexa is not able to distinguish between traffic to http:/www.apple.com/support and
http://www.apple.com/retail/. All information is reported at the web property level- i.e., at the
www.apple.com level. Therefore, we are unable to track some important sites (e.g.
news.google.com is a competitor of NYTimes.com, but does not show up as one due to this
problem). Fourth, the data excludes “secure” sites (i.e., the sites whose URLs begin with https).
Fifth, some privacy advocates have criticized Alexa.com for being too intrusive and some have
even called it spyware. This may have led to some self-selection effects with those who are
paranoid about their privacy not adopting the toolbar.
In order to judge the relative size of these limitations, we compared the rankings for the
top 10 sites as identified by Nielsen//Net Ratings in August 2005 (home+work usage) and those
identified by Alexa.com. The results are summarized in Table 1. Six out of the top 10 Web sites
identified by Nielsen//Net Ratings were in the top 10 Alexa.com rankings. AOL.com was ranked
at 11- surely a sign of the acknowledged limitation above. As a comparison, if the median rank