Colloque du
Département d'Informatique et de recherche opérationnelle

Marco Gori University of Siena, Italy

The Bubble of Web Visibility
Promoting visibility as seen through the unique lens of search engines

The web seems like a Borgesian library with a huge amount of information. Access to this treasure is mediated by dragons who compete amongst themselves for dominance. The battleground is so hostile that few will survive---indeed, just one will likely achieve overall dominance in all but specialist corners of the library. The allegory is attractive-- except that the treasure is not private property but a public good, and the dragons must serve their own business interests rather than the public cause to compete successfully.

A vital source of information in everyday life, all the content of the web is readily available---in principle. But the predominant mode of access is through search engines, and---in practice---the view they offer is restricted. Typical queries match hundreds of thousands of documents, which search engines sort according to ranking heuristics. For pragmatic reasons users view only the highest ranked pages, which gives rise to the notion of web page "visibility" as seen through the lens provided by search engines.

In this talk, I'll briefly describe web spam techniques that are currently adopted to promote web sites, regardless the quality of the information. I claim that such a promotion might give rise to a speculative process that I call the "bubble of web visibility". Moreover, I argue that there are inherent problems with centralized ranking schemes of nowadays search engines and discuss alternative proposals.


Jeudi le 20 octobre 2005, 15h30, pavillon Aisenstadt, salle 6214
Information : Pierre L'Ecuyer  (