On Thu, Apr 30, 2009 at 6:37 PM, Peter Noerr <pno...@museglobal.com> wrote: > Some further observations. So far this threadling has mentioned only trying > to unify two different sets of identifiers. However there are a much larger > number of them out there (and even larger numbers of schemas and other > "standard-things-that-everyone-should-use-so-we-all-know-what-we-are-talking-about") > and the problem exists for any of these things (identifiers, etc.) where > there are more than one of them. So really unifying two sets of identifiers, > while very useful, is not actually going to solve much.
Well, that wasn't really my intention (although I thought it wouldn't be a bad start). What I would really prefer is that we compile these into a single vocabulary that could be used as a reference point. > > Is there any broader methodology we could approach which potentially allows > multiple unifications or (my favourite) cross-walks. (Complete unification > requires everybody agrees and sticks to it, and human history is sort of not > on that track...) And who (people and organizations) would undertake this? Realistically, we could achieve this via the NSDL MetadataRegistry and SKOS. We could have something like: <http://purl.org/DataFormat/marcxml> . <skos:prefLabel> "MARC21 XML" . . <skos:notation> "info:srw/schema/1/marcxml-v1.1" . . <skos:notation> "info:ofi/fmt:xml:xsd:MARC21" . . <skos:notation> "http://www.loc.gov/MARC21/slim" . . <skos:broader> http://purl.org/DataFormat/marc . . <skos:description> "..." . Or maybe those skos:notations should be owl:sameAs -- anyway, that's not really the point. The point is that all of these various identifiers would be valid, but we'd have a real way of knowing what they actually mean. Maybe this is what you mean by a crosswalk. > > Ross' point about a lightweight approach is necessary for any sort of > adoption, but this is a problem (which plagues all we do in federated search) > which cannot just be solved by another registry. Somebody/organisation has to > look at the identifiers or whatever and decide that two of them are identical > or, worse, only partially overlap and hence scope has to be defined. In a > syntax that all understand of course. Already in this thread we have the > sub/super case question from Karen (in a post on the openurl (or Z39.88 > <sigh> - identifiers!) listserv). And the various identifiers for MARC > (below) could easily be for MARC-XML, MARC21-ISO2709, MARCUK-ISO2709. Now > explain in words of one (computer understandable) syllable what the > differences are. This is indeed a valid point. However, the two registries that already exist have this sort of granularity there (hence why they weren't exactly describing the *same* ONIX version). I guess I'm not really as worried about this problem because I think if people actually use it, and the system is flexible and editable the semantics will be worked out. > > I'm not trying to make problems. There are problems and this is only a small > subset of them, and they confound us every day. I would love to adopt > standard definitions for these things, but which Standard? Because anyone can > produce any identifier they like, we have decided that the unification of > them has to be kept internal where we at least have control of the > unifications, even if they change pretty frequently. Right, which is why I'm feeling less discriminatory on which one is "right". -Ross.