9. The method of claim 1 , further comprising: identifying a subgraph of the transformed graph; selecting an edge from the transformed graph that is not in the subgraph; for the pair of nodes associated with the selected edge, determining if a number of paths between the pair of nodes of the selected edge in the transformed graph that include an edge from the subgraph exceeds a second threshold; and if so, adding the selected edge to the identified subgraph.
9. The method of claim 1 , further comprising: identifying a subgraph of the transformed graph; selecting an edge from the transformed graph that is not in the subgraph; for the pair of nodes associated with the selected edge, determining if a number of paths between the pair of nodes of the selected edge in the transformed graph that include an edge from the subgraph exceeds a second threshold; and if so, adding the selected edge to the identified subgraph. 11. The method of claim 9 , wherein selecting the edge from the transformed graph comprises randomly selecting an edge from the transformed graph.