- From: Carl Mattocks <carlmattocks@checkmi.com>
- Date: Mon, 11 Oct 2004 10:18:11 -0400 (EDT)
- To: "Miles, AJ \(Alistair\)" <A.J.Miles@rl.ac.uk>
- Cc: "'Bernard Vatant'" <bernard.vatant@mondeca.com>, "Stella Dextre Clarke" <sdclarke@lukehouse.demon.co.uk>, public-esw-thes@w3.org
et Al: I agree that 'Concepts never die'.. However, I am struggling with the statement that a concept is unstable is this for a 'candidate' concept ? is a slang word a 'candidate' concept ? and would it be in a thesaurus ? are you referring to the term 'deprecated' ? :-} . Addressing the question of how to note that a candidate/deprecated in one scheme, but not in another...I agree with the proposal that SKOS allows a 'Thesaurus structure (BT-NT ) to be kept independent from the indexing practices/applications ( USE-UF ) relationship that use the Thesaurus'. n.b. I am also ok using the XTM subjectindicatorref carl <quote who="Miles, AJ (Alistair)"> > > > >> Incidentally, a design question that arises (if there is >> consensus that >> making these kinds of statement is valuable) is how to >> represent the fact >> that a concept might be candidate/deprecated in one scheme, but not in >> another. >> > > Also, I think that describing the *stability* of a concept is disctinct > from > describing the *status of a concept wrt a specific scheme*. > > So I would like to be able to say (in RDF) both that: > > 'concept X is unstable' > > ... and ... > > 'concept X is a candidate in scheme Y'. >> The *requirement for stability* dictates that, once a concept has been > published, it should certainly never be deleted, and it should be altered > as > little as possible, ideally not at all. If this practise is observed, one > can to a large extent guarantee the appropriateness of indexing values > over > time. > > However, the *requirement for fitness* dictates that a concept scheme must > be allowed to evolve to reflect changing patterns of usage, perspectives > and > systems of thought. > > I would like to be able to offer a recommendation as part of the SKOS Core > guide that balances the tension between these two requirements. So far, > the > best I can come up with is something like: > > 'whenever there is pressure to significantly alter the meaning of a > concept or set of concepts, preference should be given to defining a new > concept or set of concepts, with new unique identifers, and expressing > mapping relationships between the old ('deprecated') concepts and the new > concepts.' > Here, 'deprecated' means 'do not use this concept'. An 'isReplacedBy' > statement means 'use this concept instead'. A deprecated concept is > allowed > to persist, to support the backwards compatibility of older subject > indexes. >> > Incidentally, a design question that arises (if there is consensus that > making these kinds of statement is valuable) is how to represent the fact > that a concept might be candidate/deprecated in one scheme, but not in > another. > > Al. > > >> >> > -----Original Message----- >> > From: public-esw-thes-request@w3.org >> > [mailto:public-esw-thes-request@w3.org]On Behalf Of Bernard Vatant >> > Sent: 11 October 2004 10:06 >> > To: Stella Dextre Clarke; public-esw-thes@w3.org >> > Subject: RE: candidate and deprecated concepts >> > >> > >> > >> > >> > There again, only terms are replaced, not concepts. >> > >> > Bottom line : We need here to make distinct the *declarative* >> > properties of concepts, >> > valid whatever the context of application and the >> > *procedural* properties, applicable only >> > in specific contexts of use. For example seems to me that the >> > BT-NT relationship between >> > "Tropical Fruits" and "Bananas" should be declarative, and >> > kept existing whatever the >> > context, whereas the USE-UF relationship stated in order to >> > use the Thesaurus at a broader >> > level of granularity, is procedural: you know pretty well >> > that "Tropical Fruits" and >> > "Bananas" are distinct concepts, but in a certain context of >> > application this distinction >> > is useless for whatever reason. It's different from, say, you >> > had an ancient astronomical >> > thesaurus where "Evening Star" and "Morning Star" were >> > thought as distinct concepts, and >> > you decide/discover at some point that in fact they both have >> > to be replaced by "Planet >> > Venus". In this latter case, there is actually a >> > (declarative) change in the conceptual >> > scheme. >> > It might be that the USE-UF relationship in Thesaurus is >> > sometimes used in a declarative >> > sense, and sometimes in a procedural sense, leading to some >> > ambiguities. >> > The above quoted notion of "index profile" allows to capture >> > the procedural properties for >> > various contexts, while not changing the declarative >> > properties in the (common) Thesaurus. <quote who="Miles, AJ (Alistair)"> > > Bernard wrote: >> Yes, there again, concepts never die. This is an important >> rule I've found out in topic >> map management : never delete a topic. Change its status, >> attributes, names, >> relationships, date of validity, but never delete. Once you >> have spoken about something at >> some point, this thing exists forever, at least as a subject >> of conversation :)) >> > > Yes, I think this is absolutely crucial as a recommendation. > > N.B. this is why i tried to write about explicitly concept-oriented > indexing: because if the subject-based index is built to take *concept > identifers* and not terms as indexing values, then reshuffling which term > is > the preferred label for a concept is a minor issue. It doesn't affect > document metadata, and it can be adequately represented in RDF as a > structured history note attached to a *concept*. (i.e. I see no need to > talk about 'deprecated terms'). > > However, once we do have explicitly concept-oriented subject indexes, > further change issues arise. > > Al. > > > >> -----Original Message----- >> From: public-esw-thes-request@w3.org >> [mailto:public-esw-thes-request@w3.org]On Behalf Of Bernard Vatant >> Sent: 11 October 2004 10:06 >> To: Stella Dextre Clarke; public-esw-thes@w3.org >> Subject: RE: candidate and deprecated concepts >> >> >> >> >> Stella >> >> > The difference between a deprecated concept and a >> deprecated term may >> > not be as clear as you might wish. >> >> Sure, no more than the difference between a term or a >> concept, deprecated or not :) >> >> > (And even the word "deprecated" is a >> > bit strange to me in the context of thesauri. We usually just say >> > non-preferred.) >> >> Indeed? We currently in Mondeca work for a major actor in >> legal publication (Wolters >> Kluwer Belgium), making a very intensive use of Thesauri, >> including e.g. their use for >> automatic generation of publication index. And one of the >> strong requirements of the folks >> in charge of Thesaurus management was indeed a proper >> handling of what they call >> "deprecated terms". A deprecated term is a term that used to >> be preferred, and used as >> such, and at some point of time in the history of the >> vocabulary was replaced by another >> preferred term. After "deprecation" (so to speak) the >> once-preferred, and now deprecated >> term, is kept as a synonym of the preferred term which >> replaces it. Whatever relationships >> (BT-NT, USE, ...) of the deprecated term are re-located to >> the replacing term, and >> indexation of documents is redirected. >> >> So of course a deprecated term is non-preferred, but it used >> to be, and the system keeps >> track of that if necessary. >> >> > It is unusual to drop a concept altogether. >> >> Of course the concept does not really change because the term >> is deprecated, since it's >> replaced, it's simply the preferred term for it that changes. >> Concepts never die :) >> >> > Normally one provides a lead-in entry pointing to the >> broader concept that covers the >> > scope of the preferred term that is now to be "deprecated". >> > It is conceivable that if it was decided that a large >> subject area with >> > perhaps hundreds of concepts was now out-of-scope, then all the >> > corresponding terms might be dropped without trace ( >> although this is >> > not usually recommended). The thesaurus might well be renamed or >> > rebranded to mark the transition. >> >> This is another story ... >> >> > Much more likely would be to decide that that subject area should be >> > indexed at a much shallower level of specificity. >> >> I think Thesaurus structure can (should) be kept independent >> from the indexing >> practices/applications that use the Thesaurus. See at the end >> the general remak about >> declarative vs procedural properties. Several different >> indexing applications can use the >> same Thesaurus at different levels of granularity, use or not >> use specific branches etc >> ... This is the notion of index profile (also a requirement >> of the above quoted customer). >> The index profile can be managed independently of the >> structure of the thesaurus itself. >> You can say e.g. in the profile that you only use the three >> first levels of the Thesaurus >> hierarchy, so whatever is indexed at a finer level of >> granularity will be re-indexed by >> the relevant parent. >> >> > So, for example, in a >> > thesaurus for agricultural products, it might be decided >> that tropical >> > products should no longer be covered in detail. Where >> previously you had >> > Bananas, Pineapples, Brazil nuts etc as preferred terms ( with a >> > hierarchy of BTs such as Tropical fruits all the way up to Tropical >> > products), you might leave just one term "Tropical >> products" to cover >> > all of these. In the thesaurus you would organise entries such as >> > "Bananas USE Tropical products" - perhaps hundreds of such >> entries. Now >> > where is the "deprecated concept"? All we have is one very >> broad concept >> > taking in tropical products at all levels of detail, and lots of >> > non-preferred terms. >> >> This is quite different from deprecation, it's changing the >> granularity of the Thesaurus. >> And in such a case, you could just change the indexing >> profile, saying now that "Tropical >> Products" is a "leaf term" for the indexing profile (meaning >> that everything below should >> be indexed on that term). >> >> > So the idea of a "deprecated concept" just feels a bit alien. >> >> > I don't warm, either, to the idea of a concept getting "replaced" by >> > another one, unless they are so close that you would treat >> the two as >> > quasi-synonymous. You are hardly going to replace Bananas >> with Washing >> > machines? >> >> There again, only terms are replaced, not concepts. >> >> Bottom line : We need here to make distinct the *declarative* >> properties of concepts, >> valid whatever the context of application and the >> *procedural* properties, applicable only >> in specific contexts of use. For example seems to me that the >> BT-NT relationship between >> "Tropical Fruits" and "Bananas" should be declarative, and >> kept existing whatever the >> context, whereas the USE-UF relationship stated in order to >> use the Thesaurus at a broader >> level of granularity, is procedural: you know pretty well >> that "Tropical Fruits" and >> "Bananas" are distinct concepts, but in a certain context of >> application this distinction >> is useless for whatever reason. It's different from, say, you >> had an ancient astronomical >> thesaurus where "Evening Star" and "Morning Star" were >> thought as distinct concepts, and >> you decide/discover at some point that in fact they both have >> to be replaced by "Planet >> Venus". In this latter case, there is actually a >> (declarative) change in the conceptual >> scheme. >> It might be that the USE-UF relationship in Thesaurus is >> sometimes used in a declarative >> sense, and sometimes in a procedural sense, leading to some >> ambiguities. >> The above quoted notion of "index profile" allows to capture >> the procedural properties for >> various contexts, while not changing the declarative >> properties in the (common) Thesaurus. >> >> Regards >> >> Bernard >> >> Bernard Vatant >> Senior Consultant >> Knowledge Engineering >> Mondeca - www.mondeca.com >> bernard.vatant@mondeca.com >> >> >> >> > > -- Carl Mattocks co-Chair OASIS (ISO/TS 15000) ebXMLRegistry Semantic Content SC co-Chair OASIS Business Centric Methodology TC CEO CHECKMi v/f (usa) 908 322 8715 www.CHECKMi.com Semantically Smart Compendiums (AOL) IM CarlCHECKMi
Received on Monday, 11 October 2004 14:18:12 UTC