7. The method of claim 1 , wherein identifying one or more candidate content selection criteria graphs from the database using the search query comprises identifying semantic criteria related to the plurality of entities.
7. The method of claim 1 , wherein identifying one or more candidate content selection criteria graphs from the database using the search query comprises identifying semantic criteria related to the plurality of entities. 9. The method of claim 7 , further comprising: after identifying the semantic criteria, determining the effectiveness of the semantic criteria in content selection using a metric indicative of the effectiveness of the semantic criteria.