6. The computer-storage medium of claim 1 , wherein the subject-group score is calculated by applying a saturation function to a subject-group frequency, and wherein the subject-group frequency includes both the subject frequency and the equivalent-subject frequency.
6. The computer-storage medium of claim 1 , wherein the subject-group score is calculated by applying a saturation function to a subject-group frequency, and wherein the subject-group frequency includes both the subject frequency and the equivalent-subject frequency. 7. The computer-storage medium of claim 6 , wherein the subject frequency and the equivalent subject frequency are weighted.