The study showed that very short search requests (like “distance learning” or “St John's Wort”) tend to produce more “mainstream” search results, and fewer dissenting views. The authors conclude “[A]nybody can find the controversies — if they know the right query terms. But if the top results don't reveal the controversy, it's quite easy to be lulled into the 'sunny side' of the topic and miss the more cautionary or interesting 'darker side'.”
The article has an excellent bibliography.
This study illustrates an extension of the ideas in Cass Sunstein's book Republic.com, (sample chapter), which argues that Internet-facilitated self-selection of content by users has a negative effect on democracy. [Netlawblog]