[Task] Clean definition of Characteristic inheritance

[atextor]

Is your task related to a problem? Please describe. Currently there is no clean definition of inheritance for Characteristics, i.e., whether inheritance is allowed, and if so, how it is used in modeling and what it implies. Characteristic inheritance is used implicitly in both the formal specification (c.f. for example the the definition of bamm-c:Measurement Characteristic, which includes a line such as bamm-c:Measurement rdfs:subClassOf bamm-c:Quantifiable) and in the textual specification (c.f. for example the Characteristics classes overview diagram).

Describe the solution you'd like

• The currently already used Characteristic inheritance should be made explicit in the textual specification.
• To be consistent with Entity inheritance and Property inheritance, the specification should use bamm:extends instead of rdfs:subClassOf, as this is something that is located on the model level, not the meta model level.
• The documentation should be extended with modeling examples.

[georgschmidtdumont]

Hi @atextor , IMHO we should consider extending the validation as well to ensure that for example rdfs:subClassOf is not used.

[atextor]

SDS WG discussion 2022-07-28: This issue depends on #160.

[BirgitBoss]

Yes, it is irritating, if just reading the documentation, that on the one hand side it looks like inheritance but on the other side dataType is mandatory for Characteristic but optional for Collection that is "inheriting" from Characteristic, Trait, also "inheriting" from "Characteristic" does not have a dataType at all.