According to another embodiment of the invention, an approach is provided
for estimating how a particular user would rate a particular item from a
plurality of items. The approach is applicable to any type of items,
including rental items such as movies, music and games, and the invention
is not limited to any particular type of item. One or more items from the
plurality of items that have ratings similar to the particular item are
identified. Then, one or more other users are identified that have given
ratings to the one or more items that are substantially similar to
ratings given by the particular user to the one or more items. Finally,
an estimation is made of how the particular user would rate the
particular item based upon ratings for the particular item given by the
one or more other users.