W3C home > Mailing lists > Public > public-openannotation@w3.org > January 2013

Re: New Draft comments: Multiplicity

From: Antoine Isaac <aisaac@few.vu.nl>
Date: Tue, 29 Jan 2013 21:46:13 +0100
Message-ID: <51083515.8080407@few.vu.nl>
To: public-openannotation <public-openannotation@w3.org>
On 1/29/13 5:51 PM, Robert Sanderson wrote:
> On Tue, Jan 29, 2013 at 9:30 AM, Antoine Isaac<aisaac@few.vu.nl>  wrote:
>> Yes. Btw, just checking: is this (that the description of the construct
>> should be the one of the annotation) specified in the spec?
> It is now!


>>>>>> 2. Mapping with RDF container classes.
>>> I guess that I'm hesitant to promote Bag and Alt.  If we recommend
>>> them and they go away, then we're in a mess.
>>> I think the relationship between the OA and rdf classes is (now)
>>> clear.  We should (must!) of course reassess this in any future
>>> Working Group with the RDF 1.1 WG.
>> Yes, and I think the best way not to forget about it is to note the subclass
>> mapping :-)
> In the description we now talk about "equivalent classes",

Note: as you put it below, Alt and Bag should not be equivalent classes to Choice and Composite.

> but it's
> not formalized.
> Added this to the editor's note in oa:List.


>> Even in the (really unlikely) case that Bag and Alt would be deprecated, it
>> wouldn't hurt OA so much. We're just sub-classing these classes, not
>> re-using them directly.
> True, and adding the oa:default property to Choice I think is both
> useful and helps justify the classes.
> So ... I'm not against oa:Choice rdfs:subClassOf rdf:Alt and
> oa:Composite rdfs:subClassOf rdf:Bag, but I am against it for
> oa/rdf:List (as per previous reasoning).
> Other opinions?
>>>> By the way you could treat my suggestion for the axioms "bridging"
>>>> between rdf:first/rdf:rest and oa:item.
>>> Yes... it would reduce the number of mandatory triples, at the expense
>>> of some additional client side processing.
>>> I'm not sure that we have a good enough understanding of the field at
>>> this stage to make a clear determination either way as to which is
>>> better.
>> I'd argue that mentioning the axioms is useful even if the data producers
>> are the ones in charge of applying them...
> Could you write up a paragraph or so for them? Agreed that it would be
> good to be clear, and I'm not sure that I would do them justice.

How about:
Editor's note: an algorithm to automatically derive oa:item statements from the rdf:first/rdf:list pattern could be:
  1. Create a statement [l oa:item i .] for every statement [l rdf:first i .] .
  2. Create a statement [l oa:item i .] for every chain of statements [l rdf:rest r . r oa:item i .] until no new statement can be created.

At the time of writing, however, a specific formalization was not agreed upon. As an example, the following axioms reflect the intended algorithm but may not be valid in OWL2(-DL):
rdf:first rdfs:subPropertyOf oa:item .
oa:item  owl:propertyChainAxiom  ( rdf:rest  oa:item ) .


>>> I think that everyone is happy with an Editor's Note now and
>>> re-assessing later if/when necessary?
>> Yes, but I'm in favour of a quite complete Editor's note ;-)\
> :)  Will fix based on the decision about subclassing Bag and Alt.
> Rob
Received on Tuesday, 29 January 2013 20:46:43 UTC

This archive was generated by hypermail 2.3.1 : Tuesday, 6 January 2015 20:22:03 UTC