21. The system as recited in claim 16 , wherein the lexical distribution signature module is further configured to represent each of the candidates and the query string as separate vectors.
21. The system as recited in claim 16 , wherein the lexical distribution signature module is further configured to represent each of the candidates and the query string as separate vectors. 22. The system as recited in claim 21 , wherein the vectors include words sorted by increasing frequency.