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Nate,

I agree with what you say below, but I don't think it addresses my 
concern which is about the use of blank nodes. Regardless of whether one 
has a URI value or a literal value, a node can be named or blank. I know 
that there is a tendency to "go blank" when punting on the decision 
URI/literal, but then you need to make some other adjustments in your 
design. As I've already shown, the use of label in multiple places in 
the data within blank nodes makes it very hard to retrieve the desired data:

<http://example.org/1>  a bf:Instance,
      bf:publication [
          a bf:Provider ;
          bf:providerDate "1966" ;
          bf:providerName [ a bf:Organization ; bf:label "Hamlyn" ] ;
          bf:providerPlace [ a bf:Place ; bf:label "London" ]
      ] .

The reason is that you cannot step through blank nodes to select only 
the bf:label for either bf:providerName or bf:providerPlace. This search 
does not work on triples with blank nodes:

SELECT ?subject ?label
      WHERE { ?subject bf:providerName ?bnode .
                   ?bnode bf:label ?label . }

This could be "solved" by creating specific properties for the labels, 
such as bf:providerNameLabel. However, the use of bf:label within blank 
nodes simply does not allow retrieval of the desired literals. Or it 
could be solved by using named graphs. It does, however, need to be solved.

kc




On 8/1/14, 6:34 AM, Trail, Nate wrote:
> Karen,
>
> The current transformation is incomplete in this Provider area, for a couple of reasons. I think we know we'd like to make          <bf:label>University of Michigan Press</bf:label> and          <bf:label>Ann Arbor</bf:label> into uris, but we haven't 'resolved'  where we go to look those things up reliably.
> Not all of the "Organizations"   in the MARC data are orgs; they might be imprints, or statements like "Distributed by Random House", meaning they are not supposed to be part of  bf:publication, but bf:distribution. etc.
> There is no imprint lookup service (yet), especially for historic materials.
> Provider places, as has been pointed out, lack jurisdiction, so we're left to guess that Paris is Paris, France.
> Those factors being the case, we're assuming that subsequent passes over the data will be able to more cleanly parse it and data-ify, and the bf:label could go away in favor of a uri.
>
> We have a second pass in the works that does lookups to ID.loc.gov for various controlled vocabulary, and may look up other authoritative sources. It's not ready for prime time, however.
>
> Nate
>
> -----Original Message-----
> From: Bibliographic Framework Transition Initiative Forum [mailto:[log in to unmask]] On Behalf Of Karen Coyle
> Sent: Thursday, July 31, 2014 9:03 PM
> To: [log in to unmask]
> Subject: [BIBFRAME] Blank nodes, xml, ttl was: [BIBFRAME] Proposal to handle "Providers" differently
>
> On 7/31/14, 3:30 PM, Ford, Kevin wrote:
>>> Of course, these have the "blank-node-+-label" problem again (still?).
>> _:xx and _:yy do not need to be blank nodes.  We've been using a lot of blank nodes in examples, but they do not need to be.
>>
> Kevin,
>
> You are absolutely right, they do not need to be blank nodes. However, my discovery of the issue with "bf:label" and blank nodes was on MARC records that I ran through the BIBFRAME tool [1], not in hand-coded examples. Obviously, BIBFRAME is not "done" so that tool is an approximation of what BIBFRAME could be, but there is an unfortunate reliance on blank nodes in its current state. This fact is somewhat hidden by the use of rdf/xml, and ditto the email examples in turtle, since blank nodes basically disappear in these notations. The proof of the pudding is in the triples. Here is a segment of real BIBFRAME instance data (as transformed from MARC by the BF tool, then converted to turtle and triples using rapper):
>
> **RDFXML:
>
> <bf:publication>
>     <bf:Provider>
>       <bf:providerName>
>         <bf:Organization>
>           <bf:label>University of Michigan Press</bf:label>
>         </bf:Organization>
>       </bf:providerName>
>       <bf:providerPlace>
>         <bf:Place>
>           <bf:label>Ann Arbor</bf:label>
>         </bf:Place>
>       </bf:providerPlace>
>       <bf:providerDate>1995</bf:providerDate>
>     </bf:Provider>
> </bf:publication>
> </rdf>
>
> **turtle:
>
>       bf:publication [
>           bf:providerDate "1995" ;
>           bf:providerName [
>               bf:label "University of Michigan Press" ;
>               a bf:Organization
>           ] ;
>           bf:providerPlace [
>               bf:label "Ann Arbor" ;
>               a bf:Place
>           ] ;
>           a bf:Provider
>       ] ;
>
> ** triples
>
> <http://bibframe.org/resources/cYO1404049290/3033010>
> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
> <http://bibframe.org/vocab/Work> .
> <http://bibframe.org/resources/cYO1404049290/3033010>
> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
> <http://bibframe.org/vocab/Text> .
> _:genid1 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
> <http://bibframe.org/vocab/Provider> .
> _:genid2 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
> <http://bibframe.org/vocab/Organization> .
> _:genid2 <http://bibframe.org/vocab/label> "University of Michigan Press" .
> _:genid1 <http://bibframe.org/vocab/providerName> _:genid2 .
> _:genid3 <http://www.w3.org/1999/02/22-rdf-syntax-ns#type>
> <http://bibframe.org/vocab/Place> .
> _:genid3 <http://bibframe.org/vocab/label> "Ann Arbor" .
> _:genid1 <http://bibframe.org/vocab/providerPlace> _:genid3 .
> _:genid1 <http://bibframe.org/vocab/providerDate> "1995" .
> <http://bibframe.org/resources/cYO1404049290/3033010>
> <http://bibframe.org/vocab/publication> _:genid1 .
>
> The blank nodes become much more visible.
>
> Many of the examples that we've seen on these recent threads don't
> actually represent "running code," or at least I couldn't transform any
> of them using tools that I have. I know this is a discussion, not a
> coding session, but I think it would be helpful to do a sanity check
> regarding what we are discussing by creating some working examples.
> It'll provide a more realistic basis for discussion.
>
> Personally, I'd like to see BIBFRAME move away from the use of blank
> nodes wherever possible, and so I'd like to see examples that don't use
> them.
>
> kc
> [1] http://bibframe.org/tools/transform/start
>

-- 
Karen Coyle
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m: 1-510-435-8234
skype: kcoylenet