Re: Trust, Context, Justification and Quintuples

On Thu, Dec 18, 2003 at 07:07:08PM -0500, Thomas B. Passin wrote:
> >Why not just reify the statement?
> 1) It is complex - you end up with four triples where all you want to
> do is to reference a statement.

How is non-standard non-triple structure less complex than a mechanism
long ago provided by the RDF standard? I think raw number of triples is
not the only measure of complexity.

> 2) The interpretation of a reified statement is not well defined.  For
> example, it is NOT a representation for any actual triple in the data
> store, and it is NOT considered "asserted"... So what is a reified
> statement and how should it relate to the other triples?

My understanding is that this question is intentionally left by the spec
up to schema and application designers. In my previous example, intended
interpretation of "ex:context" property was assertion that the triple
under question is asserted by the "http://example.com/" KB. Is there
something non-obvious or non-standard about such interpretation?

> 3) It is contorted -  if a statement had its own resource identifier,
> it would be easy and natural to refer to it as the object of an RDF
> statement.

It seems to me that your use of words "own" and "natural" in this
statement is ambiguous: I don't see a reason why these same words
wouldn't apply to my example.

> And, of course, practical RDF processing systems are likely to have
> some internal identifier, so why to make one externally available?

And why not make the internal identifier externally available as a
proper property?

Please check Samizdat to see how I handle statement (and resource) ids
and how I use reification to solve the trust problem. Unfortunately, due
to the recent Savannah compromise, it is temprorarily unavailable for
download, but I can email the 73k tarball of the latest release to
anyone who requests it.

-- 
Dmitry Borodaenko

Received on Friday, 19 December 2003 12:13:19 UTC