- From: Frank Manola <fmanola@mitre.org>
- Date: Thu, 03 Apr 2003 08:52:20 -0500
- To: Patrick.Stickler@nokia.com
- CC: gk@ninebynine.org, w3c-rdfcore-wg@w3.org
Patrick.Stickler@nokia.com wrote: > > Er... you're telling them to use plain literals in the RDF but > interpret them as typed literals by the applications. This > means that conclusions drawn from an RDF-only application about > those CC/PP statements will differ from conclusions drawn by > a CC/PP application. Yes. > > That means that non-monotonicity is being introduced between the > RDF and CC/PP layers. > > No? No. Dealing with literals this way in CC/PP may be a Bad Thing (e.g., it may create a lack of interoperable semantics with other applications), but I don't think it's properly described as non-monotonicity. It's always going to be the case that an app that uses a specialized vocabulary with built-in meaning that it understands is going to be able to draw more conclusions about graphs using that vocaulary than an RDF-only application. This is true of OWL, for example. This doesn't mean OWL is introducing non-monotonicity between the RDF and OWL layers. The same is true for specialized interpretations of schemas and literals (it's an application specific way of interpreting the RDF, just as a specialized vocabulary would be). We can still claim it's a bad idea without describing it as non-monotonicity. > > Patrick > > > >>-----Original Message----- >>From: ext Graham Klyne [mailto:gk@ninebynine.org] >>Sent: 03 April, 2003 11:03 >>To: Stickler Patrick (NMP/Tampere); w3c-rdfcore-wg@w3.org >>Subject: RE: Issue jsr-118 (global datatyping) >> >> >>At 10:36 03/04/2003 +0300, Patrick.Stickler@nokia.com wrote: >> >> >>>Please, let's not recommend that CC/PP introduce >>> >>non-monoticity between >> >>>the RDF and Application layers! >>> >>Indeed. My proposal is no such thing. >> >>#g >>-- >> >> >>>>-----Original Message----- >>>>From: ext Graham Klyne [mailto:gk@ninebynine.org] >>>>Sent: 02 April, 2003 18:26 >>>>To: w3c-rdfcore-wg@w3.org >>>>Subject: Issue jsr-118 (global datatyping) >>>> >>>> >>>> >>>>Er, how did this issue end up being assigned to concepts? >>>> >>>>Anyway, here's a proposed resolution for discussion: >>>> >>>>Rejected, or maybe postponed. >>>> >>>>[[ >>>>We have much sympathy with this request. But the working >>>>group spent much >>>>time exploring options to allow global datatyping of the kind >>>>requested >>>>here, and were unable to find a solution that allowed >>>> >>this and also >> >>>>preserved other strongly-desired features of RDF. It might >>>>be possible to >>>>devise an alternative syntax-based approach to global >>>>datatyping, but I >>>>think even that would not fully capture the goals of CC/PP >>>>here, to express >>>>capability profile feature types in a schema separately from >>>>on-the-wire >>>>profiles. >>>> >>>>The current version of CC/PP formally treats all attributes >>>>as textual >>>>values (i.e. plain literals in RDFcore parlance). The global >>>>datatyping >>>>could be achieved for CC/PP applications by continuing to >>>>formally treat >>>>all CC/PP attributes as textual values and: >>>>(a) using range constraints to limit the allowed lexical >>>> >>values, and >> >>>>(b) building the lexical-to-value mapping into the semantics >>>>of the CC/PP >>>>attribute properties. >>>> >>>>(a) would require some URIs to be designated to denote >>>>classes for the >>>>lexical space of the datatypes used. Currently, CC/PP uses >>>>its own URIs >>>>for datatypes, so this would be easily accommodated. In >>>>practical terms, I >>>>see no changes to current CC/PP applications required by this >>>>change: what >>>>is described above is a formal device to make CC/PP as >>>>currently defined be >>>>consistent with the current semantic framework. >>>> >>>>The downside of this approach is that it is a non-standard >>>>approach to >>>>using literals to indicate datatype values, and it may add >>>>some complexity >>>>if and when future developments of CC/PP require to express >>>>comparisons >>>>between CC/PP attribute values and datatype values from other >>>>RDF descriptions. >>>>]] >>>> >>>>Note to WG: the suggested CC/PP approach is basically a >>>> >>strategy for >> >>>>implementing CC/PP under the old datatyping proposal 'S', >>>>ignoring the new >>>>datatyping facilities. >>>> >>>>#g >>>> >>>> >>>>------------------- >>>>Graham Klyne >>>><GK@NineByNine.org> >>>>PGP: 0FAA 69FF C083 000B A2E9 A131 01B9 1C7A DBCA CB5E >>>> >>>> >>>> >>------------------- >>Graham Klyne >><GK@NineByNine.org> >>PGP: 0FAA 69FF C083 000B A2E9 A131 01B9 1C7A DBCA CB5E >> >> >> > -- Frank Manola The MITRE Corporation 202 Burlington Road, MS A345 Bedford, MA 01730-1420 mailto:fmanola@mitre.org voice: 781-271-8147 FAX: 781-271-875
Received on Thursday, 3 April 2003 08:31:38 UTC