- From: Patrick Stickler <patrick.stickler@nokia.com>
- Date: Thu, 11 Mar 2004 14:13:28 +0200
- To: "ext Jeremy Carroll" <jjc@hplb.hpl.hp.com>
- Cc: www-archive@w3.org, ext Chris Bizer <chris@bizer.de>, Pat Hayes <phayes@ihmc.us>
On Mar 11, 2004, at 11:28, ext Jeremy Carroll wrote: > > > I think we are agreed that: > > the choice between an asserted attribute in the XML and vocab in the > triples is an important one > > that it is not obvious which way to go I'm myself pretty much sold on the vocabulary approach. > > (Jeremy, Pat and Patrick have all argued for an asserted attribute at > some point) > > Judging by Pat's last message, at least for now, we are trying a vocab > solution. I need to read and probably reply separately to that > message. > > The obstacle of legacy RDF/XML that does not have such an attribute, > and legacy RDF/XML tools that do not support such an attribute is one > reason for using vocab, but we should try and enumerate the pros and > cons. > > > Pro XML attribute > > - very clear > - publisher has clear control > - easy solution to bootstrapping problem > > Con XML attribute > > - publisher's identity left implicit Could add yet another attribute to indicate authority. And another for a signature... > - legacy I think this is the particular nail in the coffin for this approach. > - third party assertions impossible This is a *PRO*, not a con! ;-) I think that assertion and agreement are two very different things. Just because I agree with the statements in some graph does not mean that I assert that graph (even if I myself assert another graph having the same statements). Eh? I wonder if what you really mean by rdfx:assertedBy is really more like rdfx:affirmedBy ...? > - adds additional theoretical level, isn't assertional status just > more metadata? I think we add that level for either the XML or vocab approach. > > > Pro Vocab > > - uses existing mechanisms, and hence partially addresses legacy > - enables third party assertions, Not necessarily, if the interpretation of statements employing that vocabulary to qualify a graph is limited to qualifying the graph in which they occur. Perhaps we need to split this up into Intra-Graph Vocab and Inter-Graph Vocab, the former providing for self qualifying graphs, and the latter allowing for one graph to have statements qualifying another. > or single assertion by author for many docments > - can derive assertional status, so system is extensible by users I'm not sure how you could reliably derive the intent of the author as to whether a set of statements was intended to be asserted or not. > - vocab can require publisher to be identified by a URI node Exactly how does one do this in RDF? I don't recall any facility for differentiating between URI denoted resources and bnode denoted resources in the range of a property. Does OWL provide such a distinction? This would, though, be a pro for the XML approach, in that one could have an attribute for the authority that required URI values. > (well I guess a bnode would do, but I wouldn't trust it!) Nor I, unless there was some owl:sameAs equating it to a URI that I trusted... > > Con Vocab > > - can derive assertional status so bootstrapping is complicated I would argue that this is a con for Inter-Graph vocab but not Intra-Graph vocab. > - bootstrapping is logically twisted, since we seem to need to > assume that a graph is asserted in order to examine its assertional > status One person's 'twisted' is another's 'elegant' ;-) > > > What have I forgotten? Short statements please, no advocacy. I tried... really I did... Patrick > > Jeremy > > -- Patrick Stickler Nokia, Finland patrick.stickler@nokia.com
Received on Thursday, 11 March 2004 07:13:59 UTC