Re: Possibility of an LPG-profile

One problem (of many) I see with this profile is that it would not be an LPG 
profile.  There would still be fundamental mismatches between what could be 
said in this profile and what can be said in LPGs.

peter


On 8/21/24 12:02, Lassila, Ora wrote:
> I have been thinking a lot what I would like to see in an “LPG-profile”. Here 
> are my current thoughts:
> 
> The general question, of course, is this: “Are profiles harmful for RDF-star, 
> and if they are, why?” In other words, if we define profiles, what will blow 
> up downstream?
> 
> A minimal “LPG-profile” (for the lack of better name) would be a restriction 
> on the current baseline model of RDF-star that would make the rdf:reifies 
> -property (or whatever name we ultimately choose for it) functional. In other 
> words, it would ensure that a reifier (identifier) only reifies a single 
> triple. This allows us to treat reifiers as LPG edges, and statements about 
> reifiers (i.e., statements about “triple occurrences”) would then correspond 
> to LPG edge properties. RDF is more expressive, though, allowing the objects 
> of these statements to be nodes in the RDF graph, not just literals like in 
> LPGs. This would be fine.
> 
> My questions about any of this are at least the following:
> 
> 1 – Is this a syntactic or a semantic restriction?
> 
> 2 – If we do this, or some other profile-based restriction, what are the 
> consequences for semantics (as defined in the baseline)?
> 
> 3 – Is it still possible to define entailment regimes (beyond simple 
> entailment) on top of this (RDFS & OWL, namely)? That is, can the restriction 
> be violated by way of entailments?
> 
> 4 – From the implementation standpoint, are there aspects of RDF-star we have 
> not yet considered? For example, does allowing IRIs as reifiers present a 
> burden for implementers (say, considering scenarios where a triple store 
> learns after the fact that the subject of some statements is indeed a 
> reifier)? Discussing implementation details of upcoming commercial products is 
> not easy, of course. Since an LPG-profile would be (potentially) interesting 
> to people also implementing LPG support, their implementation choices may not 
> be the same as those just implementing RDF. Your mileage may vary.
> 
> Sorry I did not get this email out earlier. I am hoping we can discuss the 
> general idea and possibility of profiles tomorrow.
> 
> Ora
> 
> -- 
> 
> Dr. Ora Lassila
> 
> Principal Technologist, Amazon Neptune
>

Received on Thursday, 22 August 2024 14:12:10 UTC