- From: Pat Hayes <phayes@ihmc.us>
- Date: Fri, 8 Jun 2012 22:53:06 -0500
- To: "Peter F. Patel-Schneider" <pfpschneider@gmail.com>
- Cc: Steve Harris <steve.harris@garlik.com>, Richard Cyganiak <richard@cyganiak.de>, Dan Brickley <danbri@danbri.org>, Guus Schreiber <guus.schreiber@vu.nl>, RDF WG <public-rdf-wg@w3.org>
I can't help noticing that this problem is a classical case of a single URI having multiple meanings depending on its um, context of use. Rather than depreciating this (which people apparently find useful) maybe we should admit that this phenomenon is just going to happen, and deal with it. Which we can do handily with the idea outlined in http://www.w3.org/2011/rdf-wg/wiki/AnotherSpin. Which by the way I just discovered was already suggested in its essentials by Deb McGuinness, Li Ding and Jie Bao two years ago at the RDF new directions workshop. Just sayin'. Pat On Jun 8, 2012, at 11:38 AM, Peter F. Patel-Schneider wrote: > Unfortunately this description is precisely the "attractive nuisance". > > Part of the problem of rdf:value is that gets used for lots of things, which causes problems when one wants to place restrictions (domain, range) on it for one's own use. > > Part of the problem of rdf:value is that it has no meaning on its own, so different people put different meanings on it. > > In a fundamental sense, using a single name for multiple purposes goes against the core RDF representation philosophy. To make things worse, RDFS does not have the representational expressiveness to keep these different uses from interfering with each other. > > peter > > > On 06/08/2012 12:09 PM, Steve Harris wrote: >> Exactly - hence my suggestion to defang it, and make it more like what the (english language) description sounds like. >> >> Quoting from http://www.w3.org/TR/rdf-schema/#ch_value >> >> "5.4.3 rdf:value >> >> rdf:value is an instance of rdf:Property that may be used in describing structured values. >> >> rdf:value has no meaning on its own. It is provided as a piece of vocabulary that may be used in idioms such as illustrated inexample 16 of the RDF primer [RDF-PRIMER]. Despite the lack of formal specification of the meaning of this property, there is value in defining it to encourage the use of a common idiom in examples of this kind." >> >> - Steve >> >> On 8 Jun 2012, at 16:57, Peter F. Patel-Schneider wrote: >> >>> One problem with rdf:value is that it is an "attractive nuisance". >>> >>> Developers see what appears to be a nice clean pool of water in which to place their ontology, and don't notice the acid that will eventually break it down, nor the slick walls that prevent extraction.. >>> >>> peter >>> >>> On 06/08/2012 11:49 AM, Steve Harris wrote: >>>> On 8 Jun 2012, at 09:51, Richard Cyganiak wrote: >>>> >>>>> On 6 Jun 2012, at 18:31, Peter F. Patel-Schneider wrote: >>>>>> Yes, I know that there are examples of rdf:value being used in n-ary relations and structured objects. They all look like disasters-in-waiting. >>>>> +1. >>>>> >>>>> I've never seen a use of rdf:value that isn't an anti-pattern. >>>>> >>>>> In n-ary relations you want to declare the range of the value, and you can't do that for rdf:value (because you'd get clashing range declarations). The rdf:value property is inappropriate for modeling n-ary relations. >>>>> >>>>> I still think that rdf:value ought to be deprecated. >>>> Or, just redefine it to match what people actually use it for? >>>> >>>> If there's genuinely no kosher uses of it in the wild, that ought to be harmless, and user-friendly. >>>> >>>> Regards, >>>> Steve >>>> > > ------------------------------------------------------------ IHMC (850)434 8903 or (650)494 3973 40 South Alcaniz St. (850)202 4416 office Pensacola (850)202 4440 fax FL 32502 (850)291 0667 mobile phayesAT-SIGNihmc.us http://www.ihmc.us/users/phayes
Received on Saturday, 9 June 2012 03:53:45 UTC