Head Entities are entities within a knowledge graph that are more regularly referenced, linked to, downloaded, and utilized than other entities. An example of a head entity can be seen in a Fortune 1000 company with many subsidiaries, product lines, and news mentions. The relationship between head and tail entities can be seen at the micro and macro levels of knowledge graphs
At the micro level, head entities may also refer to the subject of a fact. Part of the creation of records for assimilation into knowledge graph entities involves the parsing of facts into head, relation, and tail components (alternatively, subject, predicate, and object components). Take the sentence “Einstein won the Nobel Prize” as an example. “Einstein” would function as the head entity, “winner of” could function as a relationship, and “Nobel Prize” as the tail.
See the related term “Long Tail” for more information.