- From: Graham Klyne <GK@dial.pipex.com>
- Date: Thu, 25 May 2000 10:10:38 +0100
- To: "McBride, Brian" <bwm@hplb.hpl.hp.com>
- Cc: "'guha@guha.com'" <guha@guha.com>, RDF interest group <www-rdf-interest@w3.org>
Brian, What I am trying to accomplish is to find a *representation* (as opposed to implementation), within the RDF model (as opposed to serialization), for trust-related information. Who signed what statements, etc. I think this is a general problem, so it is appropriate to seek a "standardized" form for representing such information rather than to have each application of RDF invent its own solution. I think we may be trying to say the same thing, or something very similar. Certainly, Guha's comments about representing contexts as resources seem entirely consistent with what I was trying to suggest. Unfortunately, I find XML serialization of RDF is very difficult to read, and not helped by the HTML formatting of your message, so I can't tell exactly what you propose in your message. It looks as if you are suggesting something similar to Sergey's proposal that I reference from my original posting. Thus, if there is a difference between our proposals, I think it is that I am seeing a 'context' as a property of a statement, where you seem to suggest a statement is a property of a 'statementset'. In either case, we need a way to represent a statement (preferably without invoking the machinery of reification). So, an additional ingredient in my suggestion (and Sergey's) is the use of a digest function to represent a statement. (The details of how to compute a digest are TBD -- and, yes, anonymous resources may pose a challenge.) I would find it easier to understand your thinking if you could show your view of an RDF graph representing a collection of statements that have been signed by an identified person. #g -- At 06:53 PM 5/24/00 +0100, McBride, Brian wrote: >I'm not sure what you are trying to accomplish here Graham. If you are >looking for an implementation, consistent with the current RDF specs that >will do the job, then I don't think any extra machinery is needed. Have a >look at the bit about StatementSet's in: > >http://lists.w3.org/Archives/Public/www-rdf-interest/2000May/0013.html > > >This is I think just what Guha has described. > >I'm also not sure how one computes a digest for a statement which refers to >an anonymous resource > >If you are looking to extend the model to support context's without the >percieved bloat that results from reification, then could one just declare >statements to be resources. This is in fact what reification does, but >might be a more palatable way of explaining it. > >Brian > > > >-----Original Message----- > >From: Guha [mailto:guha@guha.com] > >Sent: Wednesday, May 24, 2000 17:26 > >To: Graham Klyne > >Cc: RDF interest group > >Subject: Re: Representing trust (and other context) in RDF > > > > > >The way the AI folks have been modelling contexts --- > > > >if source--arc-->target (written as arc(source, target)) > >is in context C, you write it as ist(C, arc(source, target)). > >"ist" is read as "is True In". > > > >C is itself a first class object (i.e., a resource). The collection > >of statements that are true in C could be closed under > >deduction. > > > >The common frameworks for contexts allow for lifting > >of statements from one context to another. i.e., if a statement > >P is true in C1, one can conclude that it is true in C2. > > > >Guha ------------ Graham Klyne (GK@ACM.ORG)
Received on Thursday, 25 May 2000 06:49:05 UTC