Re: JSON and Lists

question inline

regards, Frederick

Frederick Hirsch, Nokia
Co-Chair W3C Web Annotation WG
@fjhirsch



On Oct 24, 2014, at 7:46 AM, Robert Sanderson <azaroth42@gmail.com> wrote:

> 
> I agree with Stian.  The existence of the oa:Choice resource (or oa:List separate from the head node of the rdf:List) is the important aspect, and with it the semantics are pretty clear. If the target is a Choice, then the annotation's bodies are about a resource that has several possible URIs by which it is identified, any of which are appropriate to use and potentially some are better than others.    
> 
> I think that Choice can be thought of as an abstract resource that identifies a conceptual collection of interchangeable resources, such as a book that has multiple URIs where representations are available.  This is the same way that an oa:Composite or oa:List can be thought of as an abstract resource that identifies a conceptual collection of resources, but without the interchangeableness. 
> 
> 
> In terms of the direct link, previous discussion on that topic went along the lines of:
> 
> * It would be nice to have a relationship from the annotation to all of the full URIs for the targets and ditto for the bodies, as they can be quite deep down in the graph
> * Systems (either client or server) can add in that property if it's useful locally, or an API function could give direct access to them.  
> * But you couldn't use SPARQL if you didn't know the non-standard property

Why isn’t it possible to have the simpler representation if we are clear how it could be mapped to the fuller tree representation? Then direct use would be simpler, but hidden could be the alternate representation allowing RDF and SPARQL processing… I guess it depends on the clarity of the definition.


> * Optimizing for a particular technology isn't a priority, compared to cluttering up all of the representations to be transferred over the wire, as it turns something that's almost always a tree into something that's almost always a graph.
> 
> 
> HTH, and apologies for radio silence -- I've had limited access this week.
> 
> Rob
> 
> 
> On Fri, Oct 24, 2014 at 10:43 AM, Stian Soiland-Reyes <soiland-reyes@cs.manchester.ac.uk> wrote:
> I think the semantics are clear. You are annotating not the list of resources, but an oa:Choice between resources. The available choices are detailed with a list - related using our own property oa:members.   
> 
> It might be an issue that tthere is no direct link from the annotation to the underlying resources - independent of any choice or specific resource and so on. This can be solved by having a new superproperty and some property chains. No idea what to call it... oa:involvedInAnnotation or something. (And in which direction should it go?)
> 
> 
> 
> 
> 
> On 23 October 2014 21:05, Jacob Jett <jgjett@gmail.com> wrote:
> This sounds fine to me from the developer / serialization view point. 
> 
> I do have a more conceptual question though. Does it change the semantics of what is being annotated? Are we annotating a list rather than the things in it? 
> 
> This might not actually be a change, since it seems like the original model is annotating a choice rather than the choices. Probably this makes no difference (kind of like annotation properties in OWL).
> 
> But I am curious about the implications for tools that leverage semantics.
> 
> Regards,
> 
> Jacob
> 
> 
> On Thu, Oct 23, 2014 at 2:34 PM, Frederick Hirsch <w3c@fjhirsch.com> wrote:
> +1  (developer usability/comprehension)
> 
> Nothing is lost and some simplification is gained, it appears.
> 
> regards, Frederick
> 
> Frederick Hirsch, Nokia
> Co-Chair W3C Web Annotation WG
> @fjhirsch
> 
> 
> 
> On Oct 20, 2014, at 4:56 AM, Ivan Herman <ivan@w3.org> wrote:
> 
> > That definitely looks like a better option to me.
> >
> > Ivan
> >
> > On 18 Oct 2014, at 03:22 , Robert Sanderson <azaroth42@gmail.com> wrote:
> >
> >>
> >> Dear all,
> >>
> >> The current OA model is less intuitive than it could easily be when it comes to the Multiplicity constructs.  For the FPWD, I think it would be beneficial to make them easier to understand and implement.
> >>
> >> The proposed structure for the oa:Choice is:
> >>
> >>  {
> >>    "@type": "oa:Choice",
> >>    "members": ["eg:body1", "eg:body2", "eg:body3"]
> >>  }
> >> Where the members are ordered in descending priority.
> >> (or "items" or other convenient name tbd)
> >>
> >> And the exact same structure for oa:List:
> >>
> >>  {
> >>    "@type": "oa:List",
> >>    "members": ["eg:target1", "eg:target2", "eg:target3]
> >>  }
> >> Where the members are ordered.
> >>
> >> This looks like something that a developer would create using JSON, when it needed to go into an object (which it does, given the distinction between List and Choice, and that the object of the hasTarget property must be an object) [see Issue 12]
> >>
> >>
> >> Conversely, the current structures expose a lot of the RDF plumbing where they shouldn't:
> >>
> >>  {
> >>   "@type": "oa:Choice",
> >>   "default": "eg:body1",
> >>   "item" : ["eg:body3", "eg:body2"]
> >>  }
> >> Where item is two separate triples, and thus the order is not deterministic.
> >>
> >> And worse for list:
> >>
> >>  {
> >>   "@type": ["oa:List", "rdf:List"],
> >>   "first": "eg:target1",
> >>   "rest": ["eg:target2", "eg:target3"],
> >>   "item" : [ "eg:target2", "eg:target1", "eg:target3"]
> >>  }
> >> Where, again, the order of the entries in item is not deterministic as they're separate triples.
> >>
> >>
> >> Thoughts?  Jacob, please feel free to describe your counter proposal from issue 1 if you'd like :)
> >>
> >>
> >> This is related to issues:
> >>  https://github.com/w3c/web-annotation/issues/1
> >>  https://github.com/w3c/web-annotation/issues/2
> >>  https://github.com/w3c/web-annotation/issues/5
> >>  https://github.com/w3c/web-annotation/issues/12
> >>
> >> --
> >> Rob Sanderson
> >> Technology Collaboration Facilitator
> >> Digital Library Systems and Services
> >> Stanford, CA 94305
> >
> >
> > ----
> > Ivan Herman, W3C
> > Digital Publishing Activity Lead
> > Home: http://www.w3.org/People/Ivan/
> > mobile: +31-641044153
> > GPG: 0x343F1A3D
> > WebID: http://www.ivan-herman.net/foaf#me
> >
> >
> >
> >
> >
> 
> 
> 
> 
> 
> 
> -- 
> Stian Soiland-Reyes, myGrid team
> School of Computer Science
> The University of Manchester
> http://soiland-reyes.com/stian/work/ http://orcid.org/0000-0001-9842-9718
> 
> 
> 
> -- 
> Rob Sanderson
> Technology Collaboration Facilitator
> Digital Library Systems and Services
> Stanford, CA 94305