RE: [ALL] review of n-ary relations

About URLs use, in the "Pattern 2" example (purchase) it would be good to avoid using of
the same fragment identifier for properties and classes with a simple case/Case
difference, like "#purpose" vs "#Purpose", and "#object" vs "#Object".
This does not help much to have people clarify the difference between property and class,
let alone that casual readers (both human and machines) are not always case-sensitive. I
know this is an usual practice in (lazy?) modeling, but I think we should not implicitly
approve it as a good practice.

I suggest to use instead the usual "#hasObject" , "#hasPurpose" for the properties, and
"#isObject" , "#isPurpose" for the inverse ones.



Bernard

Bernard Vatant
Senior Consultant
Knowledge Engineering
Mondeca - www.mondeca.com
bernard.vatant@mondeca.com


> -----Message d'origine-----
> De : public-swbp-wg-request@w3.org
> [mailto:public-swbp-wg-request@w3.org]De la part de Jeremy Carroll
> Envoye : mardi 6 juillet 2004 12:08
> A : SWBPD
> Objet : [ALL] review of n-ary relations
>
>
>
>
> Summary: ready to publish, a few comments ...
>
> While I have some comments, none are I believe showstoppers, although I
> think I should draw three comments to the WG attention in case others
> would like them addressed before first publication.
>
> These are:
> [A] use of skolemization instead of blank nodes
> [B] use of amazon.com instead of books.example.com
> [C] references not in W3C house style
>
>
> I have a number of other comments below, which can be treated as
> editorially.
>
> Expanding on these three points.
>
> [A] use of skolemization instead of blank nodes
> ===============================================
>
> In all the examples the instances of the relationships are given URIs
> such as (in N3)
>
> :Diagnosis_Relation_1
>
>
> This has two problems:
> 1) Introducing a URI node for a concept which is really only an
> existential introduces false negatives in entailment.
>
> e.g.
>
> :Christine      a       :Person ;      :has_diagnosis
> :Diagnosis_Relation_1 .
>
> :Diagnosis_Relation_1      a       :Diagnosis_Relation ;
> :diagnosis_probability :HIGH;      :diagnosis_value :Breast_Cancer .
>
> neither entails nor is entailed by
>
> :Christine      a       :Person ;      :has_diagnosis
> :Diagnosis_Relation_2 .
>
> :Diagnosis_Relation_2      a       :Diagnosis_Relation ;
> :diagnosis_probability :HIGH;      :diagnosis_value :Breast_Cancer .
>
> Despite the fact that the two have identical intention.
>
> Replacing the skolemized name ":Diagnosis_Relation_1" with a blank node
> "_:Diagnosis_Relation_1" resolves this.
>
>
>
> 2) it is in the same namespace as the ontology, see editorial notes below.
>
>
> [B] use of amazon.com instead of books.example.com
> ===================================================
>
> Personally I prefer avoiding any reference and any URL to something
> which is not an example.{com,org,net,edu} URL see RFC 2606,
> http://www.faqs.org/rfcs/rfc2606.html, except where necessary (e.g.
> w3.org URLs).
>
> The text refers to amazon.com whereas say books.example.com would be
> just as intelligible and not be open to misinterpretation as endorsing
> one company over another.
>
> (However, I do not believe this is W3C policy, unless Ralph corrects me)
>
> Further examples of URIs I don't like are in the example files where
> URIs starting http://protege.stanford.edu/ could be seen as endorsing
> protege rather than other tools. I think a w3.org URI would be more
> appropriate, in WG space, for these WG examples.
>
>
> [C] references not in W3C house style
> =====================================
>
> The references section at the end of the doc is very minimalistic. In my
> view this is acceptable in a first WD, but at some point it will need to
> be converted to the W3C house style (see any Rec for an example, best to
> go for a recent Rec)
>
>
>
>
>
> Further comments
> ================
> [[ *NONE* of my comments need to be addressed for first publish WD.
> However I would like the TF and editors to consider these comments in
> good time ]]
>
>
> I found it slightly disappointing that two out of the three examples
> were medical. I think it would be easy to replace example 2 by an
> example from a different domain than example 1 and example 3.
>
> RDF reification: I think the sentence referring the interested reader to
>   the discussion of reification in RDF could be deleted. However, others
> in the WG may disagree, and if the editors were to follow my preference,
> it would be worth drawing WGs attention to this change.
>
> The examples are in the turtle subset of N3 (I think) however this
> should be made explicit, with a reference to N3.
>
> The links to the "RDF/XML" code should say
> "RDF/XML" and not "RDF/XML abbrev"
> (I perhaps flatter myself that the reason you have written "RDF/XML
> abbrev" is following the name of the RDF/XML writer that I wrote for
> Jena. This name was taken from the 'abbrevated' RDF/XML syntax in the
> RDF Model & Syntax Rec, which has been superceded by RDF Syntax
> (Revised) which does not use this term)
>
> Most of the pictures lost their right edge when I printed them off.
>
>
> A-Box and T-Box should have different namespaces.
> =================================================
>
> The typical user would be importing the ontology and creating their
> instances in their own namespace (if the TF wanted to address this then
> also the individual names for the participants in the relationship are
> impacted)
> i.e.
> in
>
> http://www.w3.org/2001/sw/BestPractices/OEP/n-aryRelations-20040623/diagnosis.owl
>
> http://protege.stanford.edu/diagnosis#diagnosis_probability
>
> is in the ontology (T Box),
> and
> http://protege.stanford.edu/diagnosis#Christine
>
> is in the A Box. In practice, we would expect these to be in different
> spaces. I suggest that the ontology should be in
>
> http://www.w3.org/2001/sw/BestPractices/n-aryRelations/diagnosis#
>
> and the A Box in
>
> http://www.w3.org/2001/sw/BestPractices/n-aryRelations/diagnosis-example#
>
> etc. for the other examples.
>
> Technical issues with example files
> ===================================
> Looking at the diagnosis files ...
>
> N3
>
> 1) the comment concerning the base URL at the top of file has no effect,
> and is just a comment
>
> 2)
>
> (Sorry I need to go now, I will complete the technical review of the
> example files later)
>
> Jeremy
>

Received on Monday, 12 July 2004 04:30:03 UTC