Relationship and RelationshipType
from @bhaugen,
Possible test cases:
- the NRP AssociationTypes (so far Child, Member, Customer, Supplier, Affiliate, Custodian, Observer, Coordinator, Sponsor, Owner, Admin, Responsible, Harvester, Trainer, Advisor, and a couple of others that won't make sense to anybody but the perpetrators),
- Enspiral relationships
- http://vocab.org/relationship/.html
- http://d-nb.info/standards/elementset/agrelon.owl
But the NRP AssociationType and the ovn/vocab RelationshipType assume symmetrical relationships, while vocab.org/relationship assumes asymmetric (one-way) relationships. So to define a symmetric relationship, they separately define each end (childOf, parentOf).
So they can't tell it's the same relationship, but on the other hand, we can't define asymmetric relationships like Follower, Like or Circled.
Do we care? Will we confuse people if our relationship is different from their relationship?
agrelon.owl contrastingly appears to define both each end of a binary relationship singly and also the combination: Combinations are classes: http://d-nb.info/standards/elementset/agrelon.owl#HasChildParent Each end is a property, and the properties specify their inverse: http://d-nb.info/standards/elementset/agrelon.owl#hasChild http://d-nb.info/standards/elementset/agrelon.owl#hasParent
Very complicated ontology. Also has class and property hierarchies, and they obviously did not read the memo about type objects...
/cc @fosterlynn