Re: RDF 1.2

Hi Hans,

On 2/15/24 04:41, hans.teijgeler@quicknet.nl wrote:
> I follow the creation struggles of RDF 1.2 and keep being puzzled why 
> people make life so difficult(to me, that is).
> 
> May I suggest something out-of-the-box?
> 
> Use N-ary relationships as Classes, with 2 to N relations (aka 
> predicates or properties), as suggested on 12 April 2006 by Natascha Noy 
> and Alan Rector in their W3C Working Group Note "Defining N-ary 
> Relations on the Semantic Web"- 
> https://www.w3.org/TR/swbp-n-aryRelations/ 

I think there are two main motivations for adding a labeled-property 
extension to RDF, in the RDF-star effort:

  - Ease of use for common use cases.  Experience with labeled property 
graphs has shown that, even though they are not as general as n-ary 
relationships, they are good enough for many common use cases.  Special 
syntax makes them easier to use.

  - Standardization.  The n-ary relationship approach requires RDF 
authors to invent their own n-ary relationships every time they want the 
effect of a labeled property.  This lack of standardization has three 
downsides:

    1. Tools cannot recognize them as the simple labeled properties that 
they were intended to be.

    2. It adds cognitive burden in authoring RDF, because the author 
needs to learn or decide which way to model them.  (Bear in mind that 
there are multiple ways that n-ary relations can be modeled in RDF.)

    3. It adds cognitive burden to readers of that RDF, who need to 
figure out that the author was really only trying to express a labeled 
property, but modeled it as a class (for example).

With that said, I confess that I have mixed feelings about the RDF-star 
approach.  On one hand, I'm glad that folks are trying to make a common 
use case easier.  But on the other hand, I wish that the problem were 
being addressed more fundamentally, to provide a *standard* but general 
way to express n-ary relations, which tools and humans could easily 
recognize.  Labeled properties should merely be a special case.

At the 2019 W3C W3C Workshop on Web Standardization for Graph Data I 
briefly outlined some ways that could be done in existing RDF, in these 
slides excerpted from one of the sessions:
http://tinyurl.com/2019NarySlides

However, even if one of those approaches for *standardizing* n-ary 
relations were done, I still think it would be worth having a convenient 
syntax for them, to reduce tedium.  I'm still hoping for that in a 
future RDF-ish syntax that would also reduce other complexities in RDF 
usage.

Thanks,
David Booth

Received on Friday, 16 February 2024 17:17:00 UTC