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Re: Use Case: "Expressing FRBR Descriptions using Named Graphs"

From: Ivan Herman <ivan@w3.org>
Date: Tue, 10 Apr 2012 15:40:30 +0200
Cc: W3C RDF WG <public-rdf-wg@w3.org>
Message-Id: <2538F638-21EC-43C3-8145-854F1F8582D7@w3.org>
To: David Wood <david@3roundstones.com>

On Apr 10, 2012, at 15:34 , David Wood wrote:

> Hi all,
> 
> On Apr 10, 2012, at 09:14, Ivan Herman wrote:
> 
>> Just my immediate reaction on this...
>> 
>> What this use case seem to demand is some possibilities to manipulate graphs explicitly, that is to create the union (in the RDF) sense of graphs (that is the way I interpret this 'Frame' concept).
>> 
>> The question is whether this is left in the application domain, via some sort of API on the RDF environment (the RDF environment I know the most, namely RDFLib, has operations to create the union of graphs)
> 
> Leaving it in the application domain was Tom's intent, I believe.  In any case, I believe that graph union rules /could/ be defined at the RDF level but /should/ probably be dealt with above RDF.
> 
>> or whether we need some declarative/syntax means for that.
> 
> Hmm, I hope we don't need a special syntax for just this use case.

Certainly not! However, we may want to express whether the Default Graph in a Dataset includes the union of the individual Graphs automatically or not. This may have an effect on inferencing and, as far as I could understand, the implementation practice out there is not uniform

Ivan


> 
> Regards,
> Dave
> 
> 
>> Something like (using Tom's pseudo-code):
>> 
>> <u> { P has_title "Moby-Dick, or, the Whale"; P has_as_subject "Whaling Ships -- Fiction" }
>> <v> { Q has_language "English" ; Q has_extent "213711 words" }
>> { 
>> <f> rdf:unionOf ( <u> <v> ) .
>> }
>> 
>> or, alternatively, some syntax that explicitly says that the Default Graph includes the union of all those graphs, but I am not sure what syntax one would use for that...
>> 
>> Ivan
>> 
>> 
>> 
>> On Apr 10, 2012, at 15:05 , Ivan Herman wrote:
>> 
>>> I am not sure all of you read the RDF Comment mailing list, so, to be on the safe side, I forward this mail...
>>> 
>>> Ivan
>>> 
>>> Begin forwarded message:
>>> 
>>>> Resent-From: public-rdf-comments@w3.org
>>>> From: Thomas Baker <tom@tombaker.org>
>>>> Subject: Use Case: "Expressing FRBR Descriptions using Named Graphs"
>>>> Date: April 4, 2012 23:44:38 GMT+02:00
>>>> To: public-rdf-comments@w3.org
>>>> Cc: Ron Murray <kandroma1@me.com>, Barbara Tillett <btil@loc.gov>, Gordon Dunsire <gordon@gordondunsire.com>
>>>> Archived-At: <http://www.w3.org/mid/20120404214438.GA47236@julius>
>>>> List-Id: <public-rdf-comments.w3.org>
>>>> 
>>>> Dear Members of the RDF Working Group,
>>>> 
>>>> The following text describes a proposed use case for Named Graphs.  For anyone
>>>> unfamiliar with "FRBR," the Wikipedia page provides a quick overview [1].  FRBR
>>>> is the foundation for RDA (Resource Description and Access), the new cataloging
>>>> standard towards which major libraries are moving [2].
>>>> 
>>>> This proposal for conceptualizing FRBR entities as Named Graphs is based on
>>>> work by Ronald Murray and Barbara Tillett of the Library of Congress.  These
>>>> ideas are illustrated in a visually very engaging slide deck, "From Moby-Dick
>>>> to Mash-Ups: Thinking About Bibliographic Networks" [3].  Gordon Dunsire has
>>>> also contributed to the proposal.
>>>> 
>>>> We would be especially grateful for feedback in advance of an event on 27 April
>>>> at the British Library [4].  The event will mark the fifth anniversary of a
>>>> meeting in May 2007 which resulted in a recommendation that RDA and FRBR be
>>>> expressed in RDF [5].  
>>>> 
>>>> The Named Graph approach outlined below is a relatively new contribution to
>>>> this ongoing thread. As the approach depends on the resolution of issues still
>>>> under discussion in the RDF Working Group, we would much appreciate your
>>>> comments or suggestions.
>>>> 
>>>> Tom
>>>> 
>>>> [1] http://en.wikipedia.org/wiki/Functional_Requirements_for_Bibliographic_Records
>>>> [2] http://en.wikipedia.org/wiki/Resource_Description_and_Access
>>>> [3] http://www.slideshare.net/RonMurray/from-mobydick-to-mashups
>>>> [4] http://dcevents.dublincore.org/index.php/BibData/fyo
>>>> [5] http://www.bl.uk/bibliographic/meeting.html
>>>> 
>>>> ----------------------------------------------------------------------
>>>> Expressing FRBR Descriptions using Named Graphs: a proposal
>>>> 
>>>> W3C's Resource Description Framework (RDF) Working Group [1] is currently
>>>> discussing proposals for supporting "named graphs" to meet a wide range of use
>>>> cases [2], possibly by extending the TriG Named Graph and RDF Data Language
>>>> [3,4].  This proposal outlines how Named Graphs might be used in resource
>>>> descriptions that are based on the so-called WEMI entities (Work, Expression,
>>>> Manifestation, and Item) of the IFLA model Functional Requirements for
>>>> Bibliographic Records (FRBR) [5].
>>>> 
>>>> This proposal views descriptions of WEMI entities as bundles of statements made
>>>> at different levels of abstraction, from the most concrete Item level to the
>>>> most abstract Work level.  Multi-level WEMI descriptions specify the
>>>> characteristics that any given Item shares with other Items at the level of
>>>> Work, Expression, and Manifestation.  Ideally, it would be possible to
>>>> incorporate descriptions of resources at the Work, Expression, and
>>>> Manifestation levels, maintained in a distributed manner by various
>>>> institutions, into the local descriptions of particular Items.  
>>>> 
>>>> Consider the following four Named Graphs, each of which is identified with a
>>>> URI (A, B, C, or D) and contains two statements:
>>>> 
>>>> -- Named Graph D, a Work-level description
>>>> P has_title         "Moby-Dick, or, the Whale"
>>>> P has_as_subject    "Whaling Ships -- Fiction"
>>>> 
>>>> -- Named Graph C, an Expression-level description
>>>> Q has_language      "English"                
>>>> Q has_extent        "213711 words"           
>>>> 
>>>> -- Named Graph B, a Manifestation-level description
>>>> R has_edition_issue "First Edition"         
>>>> R has_pub_place     "New York NY"
>>>> 
>>>> -- Named Graph A, an Item-level description
>>>> X has_OAI_ID        http://hdl.handle.net/10150/16470
>>>> X has_condition     "yellowing at page edges"
>>>> 
>>>> One might bind these four chunks into a single description by "including" them
>>>> into a common "frame":
>>>> 
>>>> FrameL includes   NamedGraphA
>>>> FrameL includes   NamedGraphB
>>>> FrameL includes   NamedGraphC
>>>> FrameL includes   NamedGraphD
>>>> 
>>>> One would then want to infer that the Item in hand (described by the statements
>>>> in Named Graph A) is _also_ described by statements in the Named Graphs at the
>>>> more abstract levels of Work, Expression, and Manifestation included in the
>>>> same Frame.  In other words, if X is the URI of the Item in hand, one would
>>>> like to infer:
>>>> 
>>>> X has_title         "Moby-Dick, or, the Whale"
>>>> X has_as_subject    "Whaling Ships -- Fiction"
>>>> X has_language      "English"                
>>>> X has_extent        "213711 words"           
>>>> X has_edition_issue "First Edition"          
>>>> X has_pub_place     "New York NY             
>>>> X has_OAI_ID        http://hdl.handle.net/10150/16470
>>>> X has_condition     "yellowing at page edges"
>>>> 
>>>> Discussion
>>>> 
>>>> 1. Formal notions of Frame, and of "inclusion" in a Frame, would need to be
>>>> defined for the general case.
>>>> 
>>>> 2. Formal rules would be needed for interpreting Frames with different
>>>> sets of FRBR descriptions, e.g., for the simple case above, in which
>>>> statements from Work-, Expression-, and Manifestation-level descriptions are
>>>> interpreted as applying to the Item.
>>>> 
>>>> 3. Given the complex, even chaotic nature of the Web, flexibility to 
>>>> implement this approach in a partial manner is a critical design criterion.
>>>> Particular WEMI descriptions should be useful in a Linked Data environment
>>>> independently of particular Frames and, ideally, even in the absence of an
>>>> understanding of Frames and Inclusion (see 1 above) or of the particular
>>>> rules applicable to FRBR (see 2 above).  In the example described above, the
>>>> statements in Named Graph D about Work P would be useful independently of
>>>> FrameL, which (according to rules yet to be defined) would merely apply
>>>> those statements, additionally, to Item X.
>>>> 
>>>> References
>>>> 
>>>> [1] http://www.w3.org/2011/rdf-wg/
>>>> [2] http://www.w3.org/2011/rdf-wg/wiki/Why_Graphs
>>>> [3] http://dvcs.w3.org/hg/rdf/raw-file/default/trig/index.html#
>>>> [4] http://lists.w3.org/Archives/Public/public-rdf-wg/2012Mar/0123.html
>>>> [5] http://www.ifla.org/VII/s13/frbr/frbr.htm
>>>> 
>>>> -- 
>>>> Tom Baker <tom@tombaker.org>
>>>> 
>>>> 
>>> 
>>> 
>>> ----
>>> Ivan Herman, W3C Semantic Web Activity Lead
>>> Home: http://www.w3.org/People/Ivan/
>>> mobile: +31-641044153
>>> FOAF: http://www.ivan-herman.net/foaf.rdf
>>> 
>>> 
>>> 
>>> 
>>> 
>> 
>> 
>> ----
>> Ivan Herman, W3C Semantic Web Activity Lead
>> Home: http://www.w3.org/People/Ivan/
>> mobile: +31-641044153
>> FOAF: http://www.ivan-herman.net/foaf.rdf
>> 
>> 
>> 
>> 
>> 
> 
> 


----
Ivan Herman, W3C Semantic Web Activity Lead
Home: http://www.w3.org/People/Ivan/
mobile: +31-641044153
FOAF: http://www.ivan-herman.net/foaf.rdf







Received on Tuesday, 10 April 2012 13:38:56 UTC

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