Membership predicate

[dr-shorthair]

Exploring the Loc-I cache, I have found

• each feature (e.g. Address, Meshblock, ContractedCatchment) is a member of a dataset, using reg:register as the membership predicate
• each linking statement is a members of a linkset, using dct:isPartOf as the membership predicate.

I'm not sure 'is part of' is exactly the right semantics - it should be 'is member of' (discrete) though that may be hair-splitting. But is there a benefit in having different predicates for membership of the two different kinds of dataset?

[jyucsiro]

Would need to check why we have different predicates used in Dataset resource vs Linkset resource. Do we consider Linkset to be a register in the same way as a Dataset?

[dr-shorthair]

We are re-using elements from a number of existing RDF vocabularies. I'm just a bit concerned that we might be picking-and-mixing most than is helpful. The most generic 'has-member' predicate is rdfs:member. AFAIK there is not common inverse for this. reg:register points the other way (from item to collection) so I see how it kinda matches the semantics, but the Registry vocabulary is not well known. Furthermore, I think I would argue that while our 'datasets' might be understood as Registers, I don't think we are using anything else from the registry model or RDF vocabulary, so I think it is a distraction to introduce it. Overenthusiasm?

I think I would be inclined to sinplify things and rely on rdfs:member for both cases (which means caching the inverse relationship and re-writing the queries around that - it is quite trivial in SPARQL at least).

[dr-shorthair]

Use of reg:register (and reg:Register) is required by pyLDAPI, but is inconsistent with the semantics of Registry Ontology. See RDFLib/pyLDAPI#17