Meeting minutes
Discuss on the open issues and PR related to semantics in the RDF-semantics document
<doerthe> w3c/
<gb> Issue 69 modification to new semantics to permit entailment that every triple term is a proposition (by pfps)
Oh.
<enrico> w3c/
<enrico> w3c/
<gb> Issue 71 Fixing the definition of instance of a graph to consider triple terms (by franconi) [spec:substantive]
<enrico> https://
<Zakim> AndyS, you wanted to ask if this definition of triple term is written done (in public) yet
<enrico> https://
<gb> Issue 49 Define an interpretation of Triple Terms (by niklasl) [needs discussion]
The "RDFS entailment for SPARQL" should be defined to have finite answers
<doerthe> but we are defining a calculus here
(a requirement of all entailment regimes)
<doerthe> it should be complete
<niklasl> rdf:_1 a rdf:Property # ...
<doerthe> question is rather is "s p o" entailed
quite - this is not the SPARQL doc on enailment regimes. this is RDF processors being accessed by SPARQL not SPARQL processors.
<enrico> yes, AndyS
<niklasl> Right, rdf:type is in RDF entailment.
<niklasl> IMHO, a triple term where the predicate does not denote a property is not a proposition; it does not exist -- i.e.it is nonsensical.
<enrico> w3c/
<gb> Pull Request 68 Add simple semantics to RDF-semantics (by franconi) [propose closing] [spec:substantive]
<enrico> to niklasl 😱
Are there any general purposed & extant SPARQL engine implementing entailment regimes? (for getting through W3C process)
<Zakim> pchampin, you wanted to point out that, if the predicate of triple terms are required to be properties, then <<( s p o )>> a rdfs:Proposition can not be inferred for arbitrary s,p,o (from the empty graph)
<enrico> w3c/
<gb> Issue 69 modification to new semantics to permit entailment that every triple term is a proposition (by pfps)
<enrico> We agree with the proposal at w3c/
<enrico> +1
<niklasl> +1
<doerthe> +1
enrico: RE is total.
<pfps> +1
enrico: implicit - always says "partial" if it is not total
<enrico> w3c/
<enrico> https://
<niklasl> the blank node trick?
<TallTed> I would prefer that nothing be implicit; that we say explicitly whatever we want others to infer
https://
<pfps> https://
https://
<Souri> Would the correct answer from SPARQL be finite for { ?s rdf:type rdfs:Resource } given an empty RDF graph?
Souri - SPARQL is based simple entailment together with a matching step - here, empty graph means results in zero rows.
<enrico> From https://
<niklasl> +1
<tl> +1
Link to rdfs14: https://
<doerthe> +1
<enrico> complete entailment patterns for RDFS:
<enrico> rdfs4a-ts, rdfs4b-ts, rdfs14
<enrico> Approximated entailment patterns in appendix A:
<enrico> if the triple structure appears in S
<enrico> sss aaa <<(xxx yyy zzz)>>
<enrico> then S RDFS entails
<enrico> sss aaa _:b.
<enrico> _:b rdf:type rdfs:Proposition.
<enrico> we do not make any claim about completeness
<enrico> at this point. Hopefully somebody will prove it
<pfps> w3c/
<gb> Issue 37 inifinite results in entailment regimes (by pfps) [spec:editorial]
<doerthe> If you don't give a sh*t about metamodelling, you don't care about the domain of RE being IRxIRxIR ;) because the IP is only used for metamodelling
<tl> i'm all for nesting - i.e. i find it really useful at least 2 levels deep -, and since implementations seem to have had no problem implementing it for RDF* i don't see why we should think about dropping this feature
<niklasl> w3c/
<gb> Issue 71 Fixing the definition of instance of a graph to consider triple terms (by franconi) [spec:substantive]
<gb> Issue 144 the term identity comparison must be defined for triple terms (by lisp)
As PFPS says - no choice points/backtracking.
<gb> Issue 150 Nature / role of triples (by pchampin)
As RDF terms bnode are concrete. Semantics may wish to write entailment equivalent.
<niklasl> The semantics now contain "the interpretation of triple terms" and "ground triple term"; may need to be looked at?
<niklasl> ... *if* 150 is decided.