Re: Question about MARCXML to Models transformation

On 3/9/11 12:02 AM, Karen Coyle wrote:
>
> Quoting Antoine Isaac <aisaac@few.vu.nl>:
>
>
>>
>> Well, if you need it such a "bibliographic blob", my two cents would be to just go for it and create this new class. But create it as a union of the classes for W, E, M or I. This is perfectly allowed, isn't it?
>>
>> And then just use OWL for representing this axiom, et voila, according to the OWL semantics [1], W is all of a sudden a subclass of your blob, and so are E, M and I. I really don't see any reason for which one could not do that.
>>
>
> FRBRCore and FRBRoo already have created a super-class of WEMI (each in
> their own way, of course:-)). FRBRer, the "version" of FRBR that should beofficially sanctioned by IFLA, does not have that and I have heard it said
> that the IFLA FRBR WG does not wish for there to be such a class. I don't
> know the reasoning behind it, and hope that someone who does know could
> bring that into the conversation.
>
> Don't the sub-classes need to be defined in relation to the super-class?
> If so, then you can't create a WEMI super-class and connect it to FRBRer
> because FRBRer WEMI would not themselves have it defined as their super-class. OR
> can you? Can you have a super-class with sub-classes even though the
> sub-classes are ignorant of the relationship?
>


Yep. Especially if they are in different namespaces/ontologies, of course.

In fact in my own experience, I've seen this recently done in the Europeana Data Model, for properties. We needed something even more generic than (a selection of) DC properties to have access to a wide variety of statement at once. So a new super-property was created for these DC properties.
Of course in the Europeana context the DC properties would "know" of their being sub-properties of this new Europeana one. But the DC spec itself does not have to mess with it--and that's quite ok as long as this new property would not become a crucial requirement for DC--which it's not.

Antoine

Received on Wednesday, 9 March 2011 12:10:28 UTC