- From: Luc Moreau <L.Moreau@ecs.soton.ac.uk>
- Date: Mon, 14 Nov 2011 06:18:35 +0000
- To: Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk>
- CC: Graham Klyne <GK@ninebynine.org>, "public-prov-wg@w3.org" <public-prov-wg@w3.org>
+1 On 14 Nov 2011, at 00:14, "Stian Soiland-Reyes" <soiland-reyes@cs.manchester.ac.uk> 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 Monday, 14 November 2011 06:19:50 UTC