Use Case: "Expressing FRBR Descriptions using Named Graphs"

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.



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
    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
    X has_condition     "yellowing at page edges"


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.



Tom Baker <>

Received on Wednesday, 4 April 2012 21:45:17 UTC