Simon,

You wrote:

> Q: In your definition, can *descriptions *be put* * into 1:1 correspondence
> with records (where a record is a atomic asserted set of propositions about
> a resource)?
>

I do not believe so, especially when referencing back to where we started -
the Marc Record.

A Marc record more often than not, contains propositions about many things:
 * The book itself (lets assume that's what the record is about) - isbn,
number of pages, cost, format, shelf location
 * The author - name, birth/death date
 * The publisher - name, location
 * Publication event - date, publisher, location
 * Subject(s)

In my view this record contains information to populate 5 or more separate
descriptions, plus the related links between them.


> On Tue, Dec 13, 2011 at 3:22 PM, Karen Coyle <[log in to unmask]> wrote:
>
>
> > Yes, I realize that you were asking Richard, but I'm a bit forward, as we
> > know.
>

Karen, thanks for diving in ;-)

I do NOT see a description as atomic in the sense that a record is
> > atomic. A record has rigid walls, a description has permeable ones. A
> > description always has the POTENTIAL to have a bit of unexpected data
> > added; a record cuts off that possibility.
>

Yes.  Take the author thing from above. It may have it's basic, Marc record
derived information, enhanced, by merging with external resources, to add
an author's website or image.


> >
> > That said, I am curious about the permeability of the edges of a named
> > graph. I don't know their degree of rigidity in terms of properties
> allowed.
> >
>
> Named graphs were supposed to be invariant under the original proposal;
>  there is a lot of mess around the semantics right now. Dan Brickley wrote
> a very nice example : http://danbri.org/words/2011/11/03/753 .
>

As per the comments on Dan's blog, it is dangerous to jump on named graphs
as the solution to perceived problems.  If I wanted to load RDF from three
separate libraries in to a triple store I would  assign them to three named
graphs, but then probably query the default global graph giving a merged
view.

Using named graphs to try to recreate our original source record seems to
defeat the [opening up] purpose of moving to Linked Data modeling in the
first place.  I also think it would add in a layer of complexity without an
obvious justifying data consumer use case.

~Richard



-- 
Richard Wallis
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