Ann,
Mostly I think I agree that the RSLP Type vocabulary may be rather
"overloaded". A few comments inserted below.
> I think if this type list were to be used as a DC recommended
> list it would need a complete overhaul.
>
> It uses the dot notation, implying some structure or even
> hierarchy to the terms. This notion was dropped long ago by
> the DC Type WG, and such hierarchies feel wrong within a
> particular property's content. Rather the type property
> should be repeated with single item for each value.
http://www.ukoln.ac.uk/metadata/rslp/types/ does say "no hierarchy is
implied by the ordering of categories".
But yes, when I started to model it in RDF a couple of months ago, I
modelled the categories separately
http://homes.ukoln.ac.uk/~lispj/rslpcd/rdf/rslptype.rdf
though I wasn't completely confident I'd got it right (and for that
reason that schema hasn't been "published" yet).
The type values all correspond to a separate rdfs:Class, and an
individual collection might be a member of multiple classes
<http://example.org/mycoll> dc:title 'My Library Book Collection' .
<http://example.org/mycoll> rdf:type rslpcldt:Collection .
<http://example.org/mycoll> rdf:type rslpcldt:Library .
<http://example.org/mycoll> rdf:type rslpcldt:Text .
> Some of the sub-terms are domain indicators eg. library,
> museum. This is not really the type of the collection. Rather
> the type of the administrator of the collection.
>
> Some of the sub-terms are the type of the items in the
> content of the collection - eg text, image - not the type of
> the collection itself. Actually I guess this is needed
> somewhere, eg to denote a collection of images.
I think I'd argue that this facet of the CLDT vocabulary at least does
fit within the semantics of the dc:type of the collection. The important
thing is that in this context the type values of CLDT are not the _same_
values as the type values from the DCMI Type Vocabulary.
i.e. the term http://purl.org/rslp/cldt#Text ("Text in the CLDT
vocabulary", or, as a QName assuming suitable namespace declarations,
rslpcldt:Text) is a different term from
http://purl.org/dc/dcmitype/Text ("Text in the DCMI Type vocabulary", or
dcmitype:Text) and has a different meaning.
i.e. <http://example.org/mycoll> rdf:type dcmitype:Text .
says that that resource is a "...resource whose content is primarily
words for reading. For example - books, letters..." etc (as specified by
DCMI). Which is not quite what I want to sat about a _collection_ of
books.
But <http://example.org/mycoll> rdf:type rslpcldt:Text .
is saying something different. Following the schema above, it says that
that resource is a "...collection of items whose contents are primarily
words for reading. For example - books, letters....". (The text on the
HTML page http://www.ukoln.ac.uk/metadata/rslp/types/ is slightly broken
there, I think.) And rslpcldt:Text is defined as a subclass of
dcmitype:Collection. It's the class of Text Collections, if you like.
> Maybe this goes in 'format'?
>
> Some of the sub-terms are about policy and use. I think this
> information should be in another property (accessRights?).
> Some seem to be repeating 'subject'.
>
> So it seems as thought Type is being used as a bucket to
> indicate a multitude of things about the collection.
>
> As the Type WG discovered, it is very difficult to devise a
> type vocabulary that everyone agrees to - and this may not be
> a very productive use of peoples' time.
>
> It would be better to suggest using existing collection type
> schemes if these exist. I'd be reluctant to support the RSLP
> list as a DC recommendation.
OK.
I can't argue that type vocabularies are difficult, and as I say, I'm
not 100% happy with CLDT.
However I do think that for an effective AP for CLD, we probably do need
to specify a suitable type scheme.
What if we adopted a vocabulary that used only the "content" types from
CLDT? i.e. those "corresponding to" (but not the same as!) the DCMI Type
Vocabulary terms (probably excluding a Collection of Collections and a
Collection of Services) :
i.e. a term to indicate that a collection is a Collection of Text items,
a term to indicate that a collection is a Collection of Image items,
a term to indicate that a collection is a Collection of Sound items,
etc etc
Pete
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