18. An article as in claim 11 , wherein the operations further comprise: ranking term frequencies based on lengths of the inverted lists retrieved from the terms inverted positional index.
18. An article as in claim 11 , wherein the operations further comprise: ranking term frequencies based on lengths of the inverted lists retrieved from the terms inverted positional index. 19. An article as in claim 18 , wherein the ranked inverted lists are searched according to the ranking and wherein the identified documents are identified according to the ranking.