7. The method of claim 1 , wherein each node in the directed acyclic graph comprises one of the plurality of tags, and each edge comprises one of the identified tag relationships.
7. The method of claim 1 , wherein each node in the directed acyclic graph comprises one of the plurality of tags, and each edge comprises one of the identified tag relationships. 8. The method of claim 7 , further comprising: creating the directed acyclic graph by: identifying any cycles in the directed acyclic graph; and collapsing all nodes in each identified cycle into a single node.