Provided are systems and methods for generating a hierarchy. In one example, a method includes receiving a first data graph including a plurality of nodes and links connecting the plurality of nodes, receiving a second data graph including a second plurality of nodes and links connecting the second plurality of nodes, generating a hierarchy based on the first data graph and the second data graph, where the generated hierarchy includes a plurality of levels, nodes from the first data graph arranged on at least one level, nodes from the second data graph arranged on at least one other level, and links connecting the nodes from the first data graph and the nodes from the second data graph, and indicating a relationships between the first and second data items, and outputting the generated hierarchy for at least one of display and further processing.