Re: lack of support for claims regarding Concise Bounded Descriptions (see MSGs)

From: Giovanni Tummarello <giovanni@wup.it>
Subject: Re: lack of support for claims regarding Concise Bounded Descriptions (see MSGs)
Date: Sun, 05 Jun 2005 17:38:13 +0200

> Hi peter, please take a look at our work [1] (this is the most concise) 
> which is the base of our P2P algorithm for partial knowledge replication 
> ([2])
> we partly got inspiration from CBD but pushed the formalism and explored 
> the properties further, so i believe i might have an explanation for 
> what patrik intuits.

I'm looking at [1], and I am puzzled by the definition of an MSG.

The MSG of a statement that has a blank node as a subject or object is
defined in terms of the MSGs of all statements that use that blank node as
a subject or object.  This seems to me to be a self-referential definition.

> CBDs are the union of all the Minimum Self contained Graphs, "involving" 
> a starting URI. 

I don't believe that this is the case.  Consider the RDF graph

	ex:a ex:r ex:c .

The CBD of ex:c for this graph is the empty graph, but the MSG of ex:c is
the entire graph.

> MSGs can indeed be called "optimal" unders a few point 
> of view, I.e. you can transfer a whole graph one MSG at a time and 
> rebuild it correctly, you cant do it in any fine granularity or in any 
> coarser without duplicating transfers of information (or loosing some). 

You need to have a particular model of information flow for this to work
out right, though.  

> Plus some other nice property that make them rather efficent as base for 
> context (See the digital singnature stuff we have). 

> MSgs are 
> guaranteed not to interfere with other MSGs so they can be safely 
> inserted and removed, MSGs can be uniquely named leading to a few 
> intersting properties (i.e. we're working on efficent syncinc of 
> RDFGraphs, results due soon).

I don't understand what "interfere" means here.

> we just came out with a small API to demonstrate these concepts  
> http://www.dbin.org/RDFContextTools.php
> 
> I think it would be nice if Patrick agrees to incldue these theorems 
> into his work so we have a unique corpus of "uri centric" "statement 
> centric" "msg centric" way of addressing RDF data. Patrick, what do you 
> think? :-) SO we can claim "optimal" in a well defined sense
> 
> Sincerely
> GIovanni
> 
> [1] 
> http://semedia.deit.univpm.it/submissions/ESWC2005_Poster/ESWC2005_signignRDF.pdf
> [2] 
> http://giovanni.ea.unian.it/semanticweb/submissions/ISWC2004_workshop_p2p/RDFGROWth_workshopISWC2004.pdf

peter

Received on Sunday, 5 June 2005 21:36:55 UTC