1. A computer-implemented method for ranking documents, the method comprising: maintaining, in a profile associated with the user, documents selected by a user for viewing within a predetermined time period; generating at least one positive word vector using words contained in at least a segment of at least one of the documents stored in the profile; generating at least one negative word vector using words contained in at least a segment of at least one of the documents that was not selected by the user for viewing; generating document word vectors for a group of documents to be ranked; performing, using at least one processor, a vector space relationship analysis of the positive word vector, the negative word vector, and the document word vectors; ranking, using the at least one processor, the group of documents based on the performed vector space relationship analysis; classifying the documents selected by the user for viewing in predetermined categories; ranking, based on the ranked group of documents, the predetermined categories; and storing the ranked categories in the profile.