"Collaborative filtering is a technique that we all use, probably every
day, without realizing it. Before we go see a movie, go to a new
restaurant, or buy some new software, we talk to people. The people that
we talk to are people that we trust, and with whom we have agreed in the
past, we gather opinions, and then apply them to the current decision.
"The GroupLens project, and the USENET BBB in particular, take the idea
that the opinions of other people can help us make better decisions, and
apply that idea to USENET News. Because USENET is so large, and there
are so many news articles and users it would be impractical for each
person to seek out opinions on every new article that is posted. To help
you the Better Bit Bureau collects each persons opinions (in the form of
ratings) and correlates those opinions for you. The opinions are given
to you in the form of predictions for each news article."