Quoting Owen Stephens <o...@ostephens.com>:
This is why RDA worries me - because it (seems to?) suggest that we
define a schema that stands alone from everything else and that is
used by the library community. I'd prefer to see the library
community adopting the best of what already exists and then
enhancing where the existing ontologies are lacking.
I've been ruminating a bit on the ad/dis-advantages of re-use vs.
create your own then link to others. In the end, I wonder how easy it
will be to manage a metadata scheme that has cherry-picked from
existing ones, so something like:
dc:title
bibo:chapter
foaf:depiction
but NOT including all properties in those namespaces. It requires any
application to have detailed knowledge about the particular selections
made. On the other hand, something like:
myNS:title --> sameas --> dc:title
myNS:chapter --> sameas --> bibo:chapter
myNS:depiction --> sameas --> foaf:depiction
allows you to easily identify "your" properties, but at the same time
gives you the equivalents to other properties in other namespaces for
sharing. It also gives you greater stability. If the FOAF community
should (rudely) change the meaning of depiction, you could find
yourself using a property that no longer means what it should.
Instead, if you have your own namespace you can change your link to
foaf (or remove it altogether) to indicate that you now fork from that
property.
Perhaps what I perceive is that properties persist over time and
relationships can be more easily treated as relating to "now."
kc
p.s. I agree with you about RDA, but think that links could be made to
remedy that.
If we are going to have a (web of) linked data, then re-use of
ontologies and IDs is needed. For example in the work I did at the
Open University in the UK we ended up only a single property from a
specific library ontology (the draft ISBD
http://metadataregistry.org/schemaprop/show/id/1957.html "has place
of publication, production, distribution").
I think it is interesting that many of the MARC->RDF mappings so far
have adopting many of the same ontologies (although no doubt partly
because there is a 'follow the leader' element to this - or at least
there was for me when looking at the transformation at the Open
University)
Owen
Owen Stephens
Owen Stephens Consulting
Web: http://www.ostephens.com
Email: o...@ostephens.com
Telephone: 0121 288 6936
On 5 Dec 2011, at 18:56, Jonathan Rochkind wrote:
On 12/5/2011 1:40 PM, Karen Coyle wrote:
This brings up another point that I haven't fully grokked yet: the
use of MARC kept library data "consistent" across the many
thousands of libraries that had MARC-based systems.
Well, only somewhat consistent, but, yeah.
What happens if we move to RDF without a standard? Can we rely on
linking to provide interoperability without that rigid consistency
of data models?
Definitely not. I think this is a real issue. There is no magic to
"linking" or RDF that provides interoperability for free; it's all
about the vocabularies/schemata -- whether in MARC or in anything
else. (Note different national/regional library communities used
different schemata in MARC, which made interoperability infeasible
there. Some still do, although gradually people have moved to
Marc21 precisely for this reason, even when Marc21 was less
powerful than the MARC variant they started with).
That is to say, if we just used MARC's own implicit vocabularies,
but output them as RDF, sure, we'd still have consistency, although
we wouldn't really _gain_ much. On the other hand, if we switch
to a new better vocabulary -- we've got to actually switch to a new
better vocabulary. If it's just "whatever anyone wants to use",
we've made it VERY difficult to share data, which is something
pretty darn important to us.
Of course, the goal of the RDA process (or one of em) was to create
a new schema for us to consistently use. That's the library
community effort to maintain a common schema that is more powerful
and flexible than MARC. If people are using other things instead,
apparently that failed, or at least has not yet succeeded.
--
Karen Coyle
kco...@kcoyle.net http://kcoyle.net
ph: 1-510-540-7596
m: 1-510-435-8234
skype: kcoylenet
