13. The computer program product of claim 12 , wherein, for each user in the set of users, the at least one attribute comprises at least one personality trait of the user.
13. The computer program product of claim 12 , wherein, for each user in the set of users, the at least one attribute comprises at least one personality trait of the user. 17. The computer program product of claim 13 , wherein the computer readable program further causes the computing device to generate the aggregate user model at least by weighting each personality trait of each user in the set of users using a mean square weighted deviation.