- From: Dan Brickley <danbri@w3.org>
- Date: Thu, 29 Jul 2004 17:40:47 -0400
- To: Simon Price <simon.price@bristol.ac.uk>
- Cc: Phil Dawes <pdawes@users.sf.net>, www-rdf-interest@w3.org
* Simon Price <simon.price@bristol.ac.uk> [2004-07-29 21:39+0100] > Actually, I think I'll disagree with myself before anyone else does. > Taking Dan's point, the ordering could well be IFP > no URI/IFP > URI > because the URI is in no way a property of the described object whereas > all other properties are. (not sure I follow the detail of this point; perhaps 'cos URIs could be modelled as properties as far as I'm concerned... but I think we're agreeing). There's definitely some sort of sliding scale thing. In the rdfig and xml-dev threads back in 2000 where we first started calling this 'smushing', I sketched 3 categories: [[ We claim RDF is good at merging data from multiple sources; in my experience this is true. The current discussion suggests a crude taxonomy of RDF data aggregation mechanisms: (1) out-out-of-the-box aggregation ("naive graph merge") All RDF systems do this, by virtue of using URIs for identifiers to merge data from multiple sources. (2) 2nd pass node convergence ("data smushing") As discussed above, strategies that merge together RDF from multiple sources in such a way as to figure out (in some cases) where anonymously-mentioned resources are descriptions of the same thing. (3) Fancy Semantic Web inference stuff ("don't hold your breath...") As above but drawing additional conclusions based on complex rules and re-application of (2). From where I'm standing, (1) seems really handy, (2) is critical to deploying this stuff in the grubby real world where things don't have URIs, and (3) is, er, something to keep an eye on. My working hypothesis (FOAF etc., more on which another time) is that (2), ie. basic techniques for folding RDF data together even when URIs are scarse, is enough to build something pretty cool. Sure we have to make some simplifying assumptions, but then that's what the Web's all about... ]] http://lists.w3.org/Archives/Public/www-rdf-interest/2000Dec/0191.html This omits to mention (under or alongside (3)) the utility more heuristic, probabilistic approaches... Dan
Received on Thursday, 29 July 2004 17:40:53 UTC