46. The method of claim 45 , wherein either the weights are scaled or else the mathematical overlaps are scaled.
46. The method of claim 45 , wherein either the weights are scaled or else the mathematical overlaps are scaled. 48. The method of claim 46 , wherein (i) a fingerprint of a document, (ii) a fingerprint of the first piece of text or (iii) a fingerprint of a document and a fingerprint of the first piece of text only includes those topic categories whose associated weights are among a selected number of highest associated weights for that document.