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Popularity and Search Engines

[originally posted to alt.internet.search-engines 27/03/2005]

DirectHit used the idea of ranking sites by the number of click-throughs and it seems that some search engines do this as a kind of quality control for search results. Whether a user clicks on results depends on where they are in the SERPS and would be influenced by the description text and title that the search engine displays. This is not the same listing results by popularity of the website which will be influenced by direct visits and links. A ranking scheme such as this could be directly influenced by optimizers clicking on their own site - something that happens with the Alexa toolbar traffic rank.

Google monitors popularity of adsense adverts placing more popular adverts higher up even if they bid less but all clicks pass through their search engine anyway so this is easy for them. Yahoo! also seem to monitor click throughs and the related keywords. A Yahoo! link looks like this:

http://rds.yahoo.com/S=2766679/K=search+engine+optimization+book/v=2/SID=e/
l=WS1/R=2/SS=88973598/IPC=fr/SHE=0/H=1/SIG=126be47b1/EXP=1112004498/*-http%3A//www.searchengineoptimizationstrategies.com/

Google Sneaky Redirects

Google search results look like they link directly to the site but if you are running Internet Explorer some JavaScript is delivered along with the results. This detects mouseOver events and redirects any clicks via the Google server. This is what happens when you click on a link:

GET http://www.google.com/url?sa=U&start=2&q=http://www.seoinc.com/&e=7634 HTTP/1.0
Referer: http://www.google.com/search?hl=en&lr=&q=search+engine+optimization

HTTP/1.0 302 Found
Location: http://www.seoinc.com/

GET http://www.seoinc.com/ HTTP/1.0
http://www.google.com/search?hl=en&lr=&q=search+engine+optimization

The behaviour is different if you are running Mozilla or Opera so Google detects UserAgent string in the HTTP Header. If you have the Google toolbar installed with limited privacy it also tells Google what you are looking and what search terms you used irrespective of whether you use their search engine. This is one way that hidden pages are found and indexed by the Google robot. MSN Search doesn't seem to monitor click throughs.

How they use this information is open to speculation. Quality of results may be an answer which would imply results that don't get clicked on get dropped further down the SERP. Although the A9.com search engine uses the Alexa traffic rank information it doesn't use traffic rank to rank results. A9 results and Google results are identical, which makes sense as A9 are using the Google search engine.

Popularity and Search Engines

Google Sneaky Redirects

See Also