- From: Enrico Franconi <franconi@inf.unibz.it>
- Date: Sat, 28 Jan 2006 00:58:22 +0100
- To: Pat Hayes <phayes@ihmc.us>
- Cc: RDF Data Access Working Group <public-rdf-dawg@w3.org>
On 27 Jan 2006, at 22:47, Pat Hayes wrote: >> option b) >> """ >> Two basic graph patterns are graph-equivalent if they are the same >> up to bnode renaming. >> """ > > I suggest we use the informal version, but include a link to the > normative formal version already published. Its a good idea > generally to link to other specs rather than repeat content: > > Two basic graph patterns are <ahref="http://www.w3.org/TR/2004/REC- > rdf-concepts-20040210/#section-graph-equality> graph-equivalent</a> > if they are the same up to bnode renaming. I agree about choosing (b), but please note that the old definition does *not* work for BGPs because there are variables as well to map; so we can't refer to it directly (unless you say explicitly that it is the same by considering variables as well). >> 2) Definition of scoping set does not emphasise the simple fact >> that in general it is an arbitrary subset of the RDF terms. So I >> propose: >> >> """ >> A Scoping Set B is an arbitrary subset of the RDF terms. >> """ > > But this could be understood as saying that B is required to be > arbitrary, i.e. cannot be further restricted by other specs, which > would be very misleading. How about being even more explicit: > > ''''' > A scoping set B is some set of RDF terms. This is an arbitrary > parameter in this definition. The contents of B should be > restricted to correspond appropriately to different entailment > regimes. > ''''' OK for me. >> 3) Typo in the definition of scoping graphs (s/The/A/). >> >> """ >> The Scoping Graph G' for RDF graph G, is an RDF Graph that is >> graph-equivalent to G >> """ >> --> >> """ >> A Scoping Graph G' for RDF graph G, is an RDF Graph that is graph- >> equivalent to G. > > Actually that was not a typo. I prefer the definite article, to > emphasize that we are talking about a single scoping graph for all > answers. I now see this, but apparently was confusing to external readers. Can you find a better rephrasing? > I know I lost the vote, but since we are now tinkering with this > yet again, let me explain why having this clause in the definition > is a mistake. Look, I am happy that you tell us your doubts. It is not matter of voting, but to find the best technical solution. The more brains are united the better it is. > During the telecon, I thought it was just a gratuitous complication > that didn't change the effect of the definition - which would > itself have been sufficient reason to reject it - but in fact it is > broken, since it allows the bnodes in BGP to overlap with those in G'. Jos made your example explicit, and he showed that it works :-) Probably you misread the definition: we say G simply entails (G' union S(***BGP'***)) i.e., there is BGP' inside, not BGP. --e.
Received on Friday, 27 January 2006 23:58:38 UTC