Patent ID: 7194471

Claim:
A document classification system for classifying a document according to contents of the document, said document classification system comprising: input means for inputting document data of the document; analyzing means for analyzing the document data so as to obtain analysis information; vector producing means for producing a document feature vector with respect to the document data based on the analysis information; transforming function calculating means for calculating a representation transforming function used for projecting the document feature vector onto a space in which similarity between the document feature vectors is reflected with a dimensional number different from a dimensional number of the document feature vector, the transforming function calculating means calculating the representation transforming function by using an inner product calculated between the document feature vectors; vector transforming means for transforming the document feature vector by using the representation transforming function; classification means for classifying the document based on similarity between the document feature vectors transformed by the vector transforming means; and classification result storing means for storing a result of classification performed by the classification means.