23. A system for use in personalizing advertising for a user, the system comprising: one or more processing devices; and one or more storage devices storing instructions which, when executed, cause the one or more processing devices to implement: a content server configured to present documents, from a set of documents, to a user such that the user can select documents for viewing; at least one positive word vector formed using words contained in at least a segment of the documents in the set of documents that are selected by the user for viewing; at least one negative word vector formed using words contained in at least a segment of the documents in the set of documents that are not selected by the user for viewing; one or more document word vectors for at least some of the documents that were selected by the user for viewing; a ranking engine configured to: perform a vector space relationship analysis of the positive word vector, the negative word vector, and the document word vectors; establish a document rank order of the documents selected by the user for viewing based on the performed vector space relationship analysis; classify the documents selected by the user for viewing in predetermined categories; and rank the predetermined categories based on the document rank order; and an ad server, operatively coupled with the ranking engine, for presenting, to the user in a selected context, advertisements associated with the ranked categories.
23. A system for use in personalizing advertising for a user, the system comprising: one or more processing devices; and one or more storage devices storing instructions which, when executed, cause the one or more processing devices to implement: a content server configured to present documents, from a set of documents, to a user such that the user can select documents for viewing; at least one positive word vector formed using words contained in at least a segment of the documents in the set of documents that are selected by the user for viewing; at least one negative word vector formed using words contained in at least a segment of the documents in the set of documents that are not selected by the user for viewing; one or more document word vectors for at least some of the documents that were selected by the user for viewing; a ranking engine configured to: perform a vector space relationship analysis of the positive word vector, the negative word vector, and the document word vectors; establish a document rank order of the documents selected by the user for viewing based on the performed vector space relationship analysis; classify the documents selected by the user for viewing in predetermined categories; and rank the predetermined categories based on the document rank order; and an ad server, operatively coupled with the ranking engine, for presenting, to the user in a selected context, advertisements associated with the ranked categories. 30. The system of claim 23 , wherein the ranking engine is configured to perform the vector space relationship analysis by applying NaÃ¯ve Bayes techniques to the positive word vector, the negative word vector, and the document word vectors.