- From: Miles, AJ \(Alistair\) <A.J.Miles@rl.ac.uk>
- Date: Thu, 1 Mar 2007 18:19:27 -0000
- To: "SWD WG" <public-swd-wg@w3.org>
- Cc: <public-esw-thes@w3.org>
I'm sorry I will not be able to comment on this issue until the 12th of March at the earliest. I request that a resolution on this issue be postponed until the telecon of the 20th March. Thanks, Alistair. > -----Original Message----- > From: public-swd-wg-request@w3.org [mailto:public-swd-wg-request@w3.org] > On Behalf Of Guus Schreiber > Sent: 01 March 2007 14:44 > To: Jon Phipps > Cc: Antoine Isaac; Daniel Rubin; SWD WG > Subject: Re: AW: [SKOS] Proposed Resolution for ISSUE 26: > RelationshipBetweenLabels > > > > > Jon Phipps wrote: > > Hi Antoine, > > > > Yes. > > I had an amendment of this third proposal in mind. > Instead of having two properties skos:prefTerm and > skos:prefLabel, I would suggest to have just the > current one, skos:prefLabel, and removing the > range restriction (rdfs:literal). So, this means > that if one queries for the the skos:prefLabel of > a concept, one either gets a literal or a resource > with a label equal to this literal. This prevents > the use of construction rules and keeps the SKOS > vocabulary simple. The only extension to the > current SKOS vocabulary would a a class skos:Term. > > In retrospect, skos:prefTerm might have been a > better name than skos:prefLabel, but I propose to > stick with the original name for > backward-compatibility reasons. > > Guus > > PS The same holds of course for skos:altLabel. > > > > > 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/ > >> > > >> > > >> > > >> > > >> > > >> > >> > > -- > 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 18:20:28 UTC