- From: Mark van Assem <mark@cs.vu.nl>
- Date: Sat, 20 May 2006 15:44:03 +0300
- To: public-esw-thes@w3.org
- Cc: Alistair Miles <a.j.miles@rl.ac.uk>
Hi all, Alistair requested me some time ago to write a "change proposal" to document the issue of not having URIs for terms in SKOS (instead they are rdfs:Literals). Basically this is to record the trade-offs of both solutions, because we could not agree on what action to take. I am still unconvinced that it is better to not have URIs for terms, but as the SWBP WG is at its end, I will settle for just recording the issue. Alistair, can you add this to the CP list [1] (provided the text is ok)? With regards, Mark. [1]http://www.w3.org/2004/02/skos/core/proposals ---------------------------------------------------------------------- Change Proposal * Title: Additional properties of terms * Type: known requirement for which solution has trade-offs * Issue/Requirement SKOS Core uses a class skos:Concept to represent "concepts" and skos:prefLabel/skos:altLabel to represent "terms" or "labels" that represent the concept lexically. Some concept schemes that are used in practice represent additional information on terms, such as [1]: - scope notes for terms, also referring to other terms to use - lexical information about the term - scope of usage of the lexical term - etymological information - register-related information - standardization related information - local identifiers for terms - date of creation - last date of modification - term abbreviations - source of the term (if the concept scheme is built up from other sources) - definitions of terms However, because the range of skos:prefLabel/skos:altLabel is rdfs:Literal it is not possible to attach these kinds of information to terms (properties cannot have rdfs:Literal as domain). * Possible Solution(s) Provide a way to represent "terms" as instances of a class so that additional properties can be attached to them. - introduce a class skos:Term; - rename skos:prefLabel/skos:altLabel to skos:prefTerm/skos:altTerm - Change the range of these properties into skos:Term With this solution in place it is possible to provide a set of common term-centric properties in SKOS Core and/or provide superproperties that can be locally extended. * Trade-offs + less information loss in conversion of concept schemes that contain these kinds of information on terms - model becomes more complex - most retrieval purposes are already covered by the existing model (benefits of new model for information retrieval may be limited) * Proposed action Future SKOS activities should reconsider this Issue, make a definitive choice and provide an explanation of the particular choice, detailing the above mentioned trade-offs. * References [1]http://lists.w3.org/Archives/Public/public-esw-thes/2005Nov/0000.html -- Mark F.J. van Assem - Vrije Universiteit Amsterdam markREMOVE@cs.vu.nl - http://www.cs.vu.nl/~mark
Received on Saturday, 20 May 2006 12:44:07 UTC