The connectivity process takes the available hierarchies and attempts to produce a single hierarchy
(output/domain_ontology/edges_hierarchy.csv
). The seed ontology provides
the scaffolding of the domain ontology hierarchy. We assume that the seed ontology
hierarchy is provided and all seed nodes are connected to form a DAG.
For each unmapped node, we check whether there is a mapped parent of that node, and produce a direct hierarchy edge from the unmapped node to the mapped parent. The intermediate nodes in the hierarchy are dropped (unless they are also in the set of unmapped nodes). The result could be a crude approximation where granularity is lost but connectivity is established. For more details about the connectivity process, please read the docs.