Abstract: In an information filtering method, attributes included in information items are extracted and stored, and ratings relative to the information items carried out by users are stored. The users include a subject user and other users. A relationship between the ratings relative to the information items rated by the subject user and the attributes thereof and a relationship between the ratings relative to the information items rated by the other users and the attributes thereof are utilized for estimating relevances to the subject user of the information items not rated by the subject user. The estimated relevances are used to carry out recommendation or filtering-in of the information item which matches with the subject user.

Abstract: An information filtering apparatus estimates an evaluation value (suitability) of a demander with respect to an item which is not evaluated by the demander but is evaluated by users other than the demander. The information filtering apparatus estimates the suitability by studying relation among the demander and the other users with respect to an evaluation value evaluated for each item by the demander and the other users. A suitable estimating means may compute the suitability in consideration of the population density or an Leading-Edge degree. The suitability can be estimated by computing the Leading-Edge degree.