I know what "super-elements" and "sub-elements" are. But can somebody please explain what "element supertype" and "element subtype" mean, or rather, where the difference is to an ordinary case of broader and narrower element?
For example, "creator person of work" has various narrower elements (e.g. , "author person" or "artist person"), but is not called an element supertype. On the other hand, the element "sound characteristic" has various narrower elements (e.g., "playing speed") and is explicitly called an "element supertype".
The glossary isn't helpful here. It explains that "element supertype" is "a broader category of an element". But I would have said that this is also true for "creator person of work" vs. "author person". Also, the glossary adds "Use for: broader element", which implies that both have the same meaning. So, if they are the same, why have two different terms?
Also, because of the "use for", I would expect only the term "element supertype" to be used in the Toolkit. But this is obviously not the case, as under related elements, it always says "For broader elements, see ..." (regardless of whether the broader element is called an element supertype or not).
Probably I just cannot see the forest for the trees. But the only thing I've come up with so far is the idea that perhaps in practice you should rather use the subtypes instead of the supertype. However, I can easily imagine situations where one gets metadata from a non-library agency which may not be as granular as the subtypes are. Also, there are various options for recording sound characteristics in the Toolkit, so it doesn't seem to be forbidden to record information on the level of this element.
Heidrun
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Heidrun Wiesenmüller
Stuttgart Media University
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