- From: Jon Phipps <jphipps@madcreek.com>
- Date: Thu, 1 Mar 2007 08:29:47 -0500
- To: "Antoine Isaac" <aisaac@few.vu.nl>
- Cc: "Daniel Rubin" <rubin@med.stanford.edu>, "Guus Schreiber" <schreiber@cs.vu.nl>, "SWD WG" <public-swd-wg@w3.org>
Hi Antoine, Yes. And just to tie in last week's discussion that resulted in that page [1], here's a link to the last message in that thread... http://lists.w3.org/Archives/Public/public-swd-wg/2007Feb/0167.html --Jon On 3/1/07, Antoine Isaac <aisaac@few.vu.nl> wrote: > Hi, > > Just a small question. > Is this alternative solution you are discussing similar to the third > solution I had put in [1]? > > Antoine > > [1] http://www.w3.org/2006/07/SWD/wiki/SkosDesign/RelationshipsBetweenLabels > > > > > At 08:55 AM 2/28/2007, Guus Schreiber wrote: > > > > > > > >> Jon Phipps wrote: > >> > >>> Guus, > >>> It seems like a good case can be made for requiring labels to be > >>> resources and an equally good case can be made for keeping the SKOS > >>> spec as simple as possible. > >>> I have always been impressed by the practical utility of the Dublin > >>> Core approach to balancing the competing needs of complexity of design > >>> and simplicity of application by providing for a "dumber" expression > >>> of metadata as well as a more complex expression in the same format > >>> when needed. > >>> Is there any way to adopt _both_ the literal and resource approach to > >>> labels and say that... if your application requires relationships > >>> between labels then they may be expressed as resources and otherwise > >>> they may/should be expressed as literals? And then provide a normative > >>> way of expressing labels as resources that is 'compatible' with labels > >>> expressed as simple literals. > >>> Several weeks ago Alistair suggested dropping the notion of separate > >>> SKOS and SKOS-CORE brands, since there was no longer a distinction > >>> between the two. I'm wondering if perhaps this discussion presents a > >>> case for a simpler SKOS-CORE and a more complex but compatible SKOS > >>> specification. But then maybe this is no longer an option or has even > >>> worse side effects. > >> > >> > >> Well, I guess we could go down this road. It would mean that we do > >> not define ranges for skos:prefLabel and skos:altLabel. We can still > >> define a class skos:Term but do not require it to be the range of the > >> label properties. The Guide could then indicate the two patterns for > >> specifying terms. But it would also mean that we have to indicate how > >> people should manage interoperability between vocabularies using a > >> different pattern. > >> > >> The more I think of it, the more it seems like a good resolution. It > >> follows the principle of minimal commitment. Whether it should lead > >> to an distinction between a Core part and Full part (possible several > >> Full parts) is another question. I would not like to go down the OWL > >> road, introducing several dialects. I prefer just showing usage > >> patterns in the Guide. > > > > > > This is a possible solution, but then when you open the door to > > alternate practices, the next question arieses as to "best practice." > > And it also makes interoperability among different skos terminologies > > difficult. > > My feeling is that should only be a last resort if our community is > > irreconcilably divided. > > > >> Guus > >> > >>> Just tossing some ideas around... > >>> --Jon > >>> On 2/28/07, Guus Schreiber <schreiber@cs.vu.nl> wrote: > >>> > >>>> > >>>> > >>>> > >>>> Jan Henke wrote: > >>>> > Dear all, > >>>> > > >>>> > I'd like to add some arguments for the labels as classes approach: > >>>> > > >>>> >>From an OO-point of view, the subject and object of Guus' > >>>> Labelrelation can > >>>> > be seen as instances. If the same labels are used in different > >>>> contexts, we > >>>> > duplicate them, i.e. introduce an unessacary redundance. > >>>> > > >>>> > I think Guus' approach also violates the OO design heuristic > >>>> "Keep related > >>>> > data and behaviour in one place" [1], because it externalizes > >>>> some data > >>>> > although it is never used without the externalizing object (done > >>>> by the > >>>> > inverseFunctional statement). In other words, you create a > >>>> relation object > >>>> > which can only be used together with one concept c, and I think > >>>> in such a > >>>> > case it is better to put the dependent part into c and create a > >>>> reusable > >>>> > object out of the rest (i.e. the label object). > >>>> > > >>>> > Guus' approach is basically an application of the "Introducing a > >>>> new class > >>>> > for a relation" pattern [2] which I always regarded as somehow > >>>> working but > >>>> > not really as a (nice) solution. > >>>> > >>>> I'm apparently not making myself clear. Of course, > >>>> this proposal will > >>>> not win a beauty contest. Theoretically speaking, the > >>>> term-as-class approach is much cleaner and nicer; > >>>> we probably all > >>>> agree on that. I pointed in another message [1] to > >>>> the WordNet example > >>>> where we followed precisely this approach. > >>>> > >>>> However, the decision should not purely be based > >>>> on beauty, but also > >>>> on usability. Let's take an Art & Architecture > >>>> Thesaurus example [2]: > >>>> > >>>> with terms as literals: > >>>> > >>>> aat:300021503 rdf:type skos:Concept. > >>>> aat:300021503 skos:prefLabel "Impressionist". > >>>> aat:300021503 skos:altLabel "Impressionism". > >>>> > >>>> with terms as classes > >>>> > >>>> aat:300021503 rdf:type skos:Concept. > >>>> aat:300021503 skos:prefLabel aat:termURI_1. > >>>> aat:300021503 skos:altLabel aat:termURI_2. > >>>> aat:termURI_1 rdf:type skos:Term. > >>>> aat:termURI_1 rdfs:label "Impressionist". > >>>> aat:termURI_2 rdf:type skos:Term. > >>>> aat:termURI_2 rdfs:label "Impressionism". > >>>> > >>>> [omitted datatypes and language labels] > >>>> > >>>> The price you pay for terms-as-classes is > >>>> potentially three-fold: > >>>> > >>>> - more triples > >>>> - less intuitive representation for naive user > >>>> (thesaurus builder) > >>>> through the level of indirection > >>>> - the need to define a scheme for generating > >>>> URIs for all terms > >>>> > >>>> Dependent on your viewpoint this price may be low > >>>> or high and we have > >>>> to balance this with the frequency of needing to > >>>> represent term > >>>> relations and properties in the target > >>>> vocabularies for SKOS. > >>>> > >>>> So, I would like to hear arguments wrt this > >>>> balancing issue. > >>>> > >>>> Guus > >>>> > >>>> [1] > >>>> http://lists.w3.org/Archives/Public/public-swd-wg/2007Feb/0210.html > >>>> [2] > >>>> http://www.getty.edu/research/conducting_research/vocabularies/aat/ > >>>> > >>>> > Best regards > >>>> > Jan > >>>> > > >>>> > [1] http://lcm.csa.iisc.ernet.in/soft_arch/OO_Design_Heuristic.htm > >>>> > [2] http://www.w3.org/TR/swbp-n-aryRelations/#pattern1 > >>>> > > >>>> > > >>>> > > >>>> > > >>>> >> -----Ursprüngliche Nachricht----- > >>>> >> Von: public-swd-wg-request@w3.org > >>>> >> [mailto:public-swd-wg-request@w3.org] Im Auftrag von Daniel Rubin > >>>> >> Gesendet: Mittwoch, 28. Februar 2007 00:58 > >>>> >> An: Guus Schreiber; SWD WG > >>>> >> Betreff: Re: [SKOS] Proposed Resolution for ISSUE 26: > >>>> >> RelationshipBetweenLabels > >>>> >> > >>>> >> > >>>> >> At 03:42 AM 2/27/2007, Guus Schreiber wrote: > >>>> >> > >>>> >>> ISSUE-26 [1] > >>>> >>> RelationshipsBetweenLabels > >>>> >>> > >>>> >>> Considering that: > >>>> >>> - representing lexical labels as classes would lead to an > >>>> >> undesirable > >>>> >>> complication of SKOS in straightforward use cases for the > >>>> >> application > >>>> >>> of SKOS, > >>>> >> As I mentioned on the tcon today, I think that lexical labels > >>>> >> should be represented as classes, precisely because they need > >>>> >> to be able to participate in relations with other classes. I > >>>> >> do not see doing this an undesirable complication of > >>>> >> SKOS--this is an issue of what representation is needed in > >>>> >> order to express the necessary relations. > >>>> >> > >>>> >>> - representing relationships between labels is required in some > >>>> use > >>>> >>> cases, and therefore an escape mechanism should preferably > >>>> >> be available > >>>> >>> for such thesauri, > >>>> >>> > >>>> >>> I propose the WG opts for an amended version of the second > >>>> solution > >>>> >>> proposed in [2]: > >>>> >>> > >>>> >>> RESOLUTION > >>>> >>> > >>>> >>> The WG resolves to add the following classes and properties > >>>> >> to the SKOS > >>>> >>> specification [3]: > >>>> >>> > >>>> >>> - the class skos:LabelRelation > >>>> >>> - the properties skos:labelRelationSubject and > >>>> >> skos:labelRelationObject > >>>> >>> with domain LabelRelation and range rdfs:literal > >>>> >> To me, this approach adds undesirable complexity to SKOS. > >>>> >> > >>>> >> > >>>> >>> In addition, the SKOS Guide should describe guidelines for > >>>> >> SKOS users > >>>> >>> to define their label relations as specializations of > >>>> >> LabelRelation and > >>>> >>> gives examples of its intended usage. The SKOS specification > >>>> >> refrains > >>>> >>> for now to predefine specializations of LabelRelation. > >>>> >>> > >>>> >>> Contrary to the proposal in [2] the class LabelRelation is > >>>> >> not defined > >>>> >>> as a subclass of skos:Annotation (which is in any case not > >>>> >> yet part of > >>>> >>> the spec), as it is not an "annotation", but a lexical > >>>> relationship. > >>>> >>> > >>>> >>> > >>>> >>> [1] http://www.w3.org/2006/07/SWD/track/issues/26 > >>>> >>> [2] > >>>> >> http://www.w3.org/2006/07/SWD/wiki/SkosDesign/RelationshipsBet > >>>> >> weenLabels > >>>> >>> [3] http://www.w3.org/TR/swbp-skos-core-spec/ > >>>> >>> > >>>> >>> -- > >>>> >>> Vrije Universiteit Amsterdam, Computer Science > >>>> >>> De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands > >>>> >>> T: +31 20 598 7739/7718; F: +31 84 712 1446 > >>>> >>> Home page: http://www.cs.vu.nl/~guus/ > >>>> >> > >>>> >> > >>>> > > >>>> > > >>>> > >>>> -- > >>>> Vrije Universiteit Amsterdam, Computer Science > >>>> De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands > >>>> T: +31 20 598 7739/7718; F: +31 84 712 1446 > >>>> Home page: http://www.cs.vu.nl/~guus/ > >>>> > >> > >> -- > >> Vrije Universiteit Amsterdam, Computer Science > >> De Boelelaan 1081a, 1081 HV Amsterdam, The Netherlands > >> T: +31 20 598 7739/7718; F: +31 84 712 1446 > >> Home page: http://www.cs.vu.nl/~guus/ > > > > > > > > > > > >
Received on Thursday, 1 March 2007 13:30:12 UTC