Re: PROV-ISSUE-145 (Tlebo): qualified identifiers may not work well with named graphs [Data Model]

Stian,

Thanks!

I'm citing your email at http://www.w3.org/2011/prov/wiki/Using_named_graphs_to_model_Accounts#AAA

-Tim

On Nov 13, 2011, at 7:13 PM, Stian Soiland-Reyes wrote:

> On Sun, Nov 13, 2011 at 11:50, Graham Klyne <GK@ninebynine.org> wrote:
> 
>> Generally, though, I think it is not a good idea to allow different accounts
>> to use the same URI for different entities.  While accounts may contain
>> statemenbts that are specific to the account, they should also provide for
>> inferences about things (specifically, Entities) that hold outside the
>> context of an account; e.g. entity1 derivedfrom entity2, if true, should be
>> true independently of any account considered.
> 
> We can't really enforce different provenance asserters to not make
> conflicting provenance assertions in different accounts - the
> possibility of this is just a fact of life. We can advice against it,
> but not prevent it.
> 
> Just like you can't tell if I am now writing a secret book explaining
> about how Graham Klyne found the green Easter Bunny in the loft, you
> can't know that someone else is not making a contradictory provenance
> assertion about the URI which resource you are asserting something
> about.
> 
> In RDF, if you are worried about this, you can counteract this by
> minting your own fresh URIs (which can deliberately be contradicted
> once they are known) or bnodes (which are unique per document/account,
> can't as easily be crashed, but then again can't be referred to from
> other provenance accounts of your own making).
> 
> 
> An account is just that, it's one "view", "understanding" or "guess"
> of how which things happened. Two different accounts might have a
> different understanding of what exactly <http://example.com/me> means
> - and therefore have a different kind of provenance trail. These
> accounts might or might not be reconsilable, and certainly doing so
> requires some isolation of the account assertions, using named graphs
> or other scoping, like the container() and account() structures in
> PROV-ASN.
> 
> A good hint of what kind of understanding the two accounts have of the
> entity is by looking at their attributes, but ultimately there are
> still no guarantees that they are truly talking about "the same
> thing", just like you can't truly be sure who I meant if I casually
> said something about "the prime minister".
> 
> 
> -- 
> Stian Soiland-Reyes, myGrid team
> School of Computer Science
> The University of Manchester
> 
>

Received on Tuesday, 22 November 2011 15:45:34 UTC