> I do
> want to point out that there are at least two ways to reduce their numbers.
> One, don't make them to begin with. {grin} Two, reconcile them out. 
-- Yes, the first would be ideal, the second is the dirty little secret that no one talks about.

The first pass often is very blank nodey (it's Friday so we'll just start making up words).  It is then important to take a second pass and reconcile those anonymous resources with known resources (those with URIs, ideally of the HTTP variety).  This could happen as part of the first pass, but it is often common to separate these steps.

The "raw" MARC2BIBFRAME transformation generates blank nodes because it makes no attempt to create HTTP URIs nor does it try to reconcile resources.  That's a programming decision but not an architecture decision.  Those blank nodes can be converted the HTTP URIs /and/ reconciliation can be attempted.

In fact, to underscore that last point, when we generate the sample data sets, we not only convert nearly all blank nodes to HTTP URIs but we also attempt to reconcile the names and subject headings with ID.LOC.GOV.  For example:

http://bibframe.org/resources/sample-lc-2/bibframe.rdf

Yours,
Kevin


> -----Original Message-----
> From: Bibliographic Framework Transition Initiative Forum
> [mailto:[log in to unmask]] On Behalf Of [log in to unmask]
> Sent: Friday, August 01, 2014 11:13 AM
> To: [log in to unmask]
> Subject: Re: [BIBFRAME] Blank nodes, xml, ttl was: [BIBFRAME] Proposal to
> handle "Providers" differently
> 
> I'm largely in agreement about the un-desireablitlity of blank nodes. I do
> want to point out that there are at least two ways to reduce their numbers.
> One, don't make them to begin with. {grin} Two, reconcile them out. What I
> mean by that is perhaps best shown in a quick example. Let's take Karen
> Coyle's 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 .
> 
> This is the output of marc2bibframe, and it is indeed chock-full of blank
> nodes. Let's assume (just for the sake of the example) that we are going to
> use Geonames and DBpedia. (And I'm going to start using prefixes in the RDF,
> just for readability.) We might make a move like:
> 
> <http://bibframe.org/resources/cYO1404049290/3033010> rdf:type bf:Work .
> <http://bibframe.org/resources/cYO1404049290/3033010> rdf:type bf:Text .
> <http://bibframe.org/resources/cYO1404049290/3033010> bf:publication
> _:genid1 .
> _:genid1 rdf:type bf:Provider .
>  dbpedia:University_of_Michigan_Press rdf:type bf:Organization .
>  dbpedia:University_of_Michigan_Press bf:label "University of Michigan
> Press" .
> _:genid1 bf:providerName dbpedia:University_of_Michigan_Press .
> geonames:4984247 rdf:type bibframe:Place .
> geonames:4984247 bf:label "Ann Arbor" .
> _:genid1 bf:providerPlace geonames:4984247 .
> _:genid1 bf:providerDate "1995" .
> 
> (As per an earlier thread on this list, many folks would use local identifiers
> with a store of co-reference. I haven't shown that because it's not to my
> particular point, but I'm in no way arguing against it.)
> 
> That killed two blank nodes, but not the third. The claim I'm making is that it's
> not the absolute number of blank nodes coming out of an automated
> transform that should bother us. It's the number that are more-or-less
> inherent in the model, and we cannot gauge _that_ number over
> unreconciled data. We can predict it to some limited extent directly from the
> model, but we are going to produce different volumes of blank nodes by
> exercising Bibframe over different bodies of data, with different regimes of
> co-reference management, with different schemes of reconciliation, and so
> forth.
> 
> ---
> A. Soroka
> The University of Virginia Library
> 
> On Jul 31, 2014, at 9:02 PM, Karen Coyle <[log in to unmask]> wrote:
> 
> > 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
> > [log in to unmask] http://kcoyle.net
> > m: 1-510-435-8234
> > skype: kcoylenet