- From: Brian McBride <bwm@hplb.hpl.hp.com>
- Date: Tue, 14 Jan 2003 19:18:43 +0000
- To: Jan Grant <Jan.Grant@bristol.ac.uk>, RDFCore Working Group <w3c-rdfcore-wg@w3.org>
At 16:55 14/01/2003 +0000, Jan Grant wrote: >A few trivial nitpicks. Appendix A actually anticipates the only issue I >have with this document (although it basically says, "there is an issue, >we don't deal with it"). Jan, am I right in reading this as a thumbs up for last call publication without change, i.e. no showstoppers. Brian >1. Introduction > >Figure 1 already includes the denotation/addressing issue I raised in >the schema review. Is it purely accidental that Eric Miller's mailbox >is named by a URI that also lets you address mail to him? I'd guess not. >What are the conventions governing the use of such "suggestive" >addressing names? > >In other words, why does this figure have the following triple: > ><http://www.w3.org/People/EM/contact#me> ><http://www.w3.org/2000/10/swap/pim/contact#mailbox> <mailto:em@w3.org> . > >and not this: > ><http://www.w3.org/People/EM/contact#me> ><http://www.w3.org/2000/10/swap/pim/contact#mailbox> _:a . >_:a rdf:type eg:Mailbox . >_:a rdfx:uri "mailto:em@w3.org"^^<xsd:uri> . > >or this (or some variant?) > ><http://www.w3.org/People/EM/contact#me> ><http://www.w3.org/2000/10/swap/pim/contact#mailbox> "mailto:em@w3.org" . > >[Come to think of it, why a mailto: and not an imap: url?] > >Following on from the example: > >"unlike conventional hypertext, RDF URIs can refer to any identifiable >thing, including things that may not be directly retrievable on the Web" > >OK so far, but are there any distinguishing characteristics that can >tell one kind of URI from another? > >(I note that this issue is addressed to some extent in Appendix A.) > > >2.1 Basic Concepts > >The example is good, again, but has this: "In this statement, we've used >the Web page's URL (Uniform Resource Locator) to identify it." > >OK, but how do I know that's what you've done? Is there some convention, >or some magic associated with the domain of the creator property? > >In other words, there appears to be some restriction on valid >interpretations of this statement that's got something to do with the >URL labelling a resource being the address of a web page. I don't think >this is articulated anywhere. I won't belabour this point though. > >Nitpick: "the object is the words..." should be "the object is the >phrase" (currently doesn't agree on number) > > >2.2 and onwards. > >I like this. The document in general is an easy read, the pictures are >colourful and straight-forward, and there are lots of examples. The >narrative structure is good and the whole thing smacks of eloquence and >polish. A very nice job. > > >Namespace prefix definitions: there's an example which includes - > > ex:index.html dc:creator exstaff:85740 . > >Again, this tacitly ignores the fact that ex:index.html appears to name >a web page, and exstaff:85740 appears to name a person; but they both >look like URLs to me. I don't hold the primer at fault here, because >this goes on a lot in RDF in the wild (it seems) - I'd be satisfied with >some way of telling which was which. > > >2.3, Figure 6 explanatory text: > >This is not a bad stab at explaining the graph-specific identity of >blank nodes in a "see spot run" stylee :-) In addition, there follows >some excellent text about not using things that look like URLs to name >things that don't have URLs (eg, people). This is a really important >idea (blank nodes everywhere?) and it's introduced well. Hopefully it >won't get lost in passing. > >In fact, it's worthwhile considering if this idea (obvious as it may >seem) isn't worth extracting into a separate note, because it's really, >really important, and Eric and Frank have done a good job of explaining >it. > > >2.5. Concepts summary > >Nitpick (numbering format change in heading) > > >4.1 RDF Containers > >Example 14 and Figure 15 contains example1.org and example2.org domains: >are these reserved for example use? How about ftp1.example.org, etc? > > >4.4 rdf:value > >I'm really uncertain whether rdf:value deserves the excellent treatment >here. It seems to me that other modelling approaches are more likely to >be successful in the long run (eg, factoring units into the property >definitions, so "exterms:weight" is defined as "weight in kilogrammes"), >although I'm ready to be set straight on that point (I've a sneaking >suspicion that there may be reasonable counterexamples in the iCalendar >world). I'd like at least to see an alternative mentioned (although >perhaps the primer isn't the place for this). > > >5.3 Interpreting RDF Schema Declarations > >Another eloquent exposition of an important thesis. Last paragraph is >one of those that'd definitely have to be in one of those mythical >cut-down "views" of the primer text :-) > > >6.1 Dublin Core > >The dc:subject is an rdf:Bag in the example. I'm _still_ not sure what >this means, particularly given the description of rdf containers >previously in the document (the prose related to the example in 4.1 >concerning a rules committee would seem to imply that the rdf:Bag should >not have been used). I seem to recall discussing this around in circles >before now; I don't recall the conclusion. > > >6.2 PRISM > >"For example, dc:date is extended by properties like >prism:publicationTime, ..." Technically, isn't it restricted or >constrained, not extended? Maybe "speciali[sz]ed"? > > >Appendix A. > >"People sometimes use RDF together with a convention that, when a URIref >is used to identify an RDF resource, a page containing descriptive >information about that resource will be placed on the web "at" that >URI...However, this convention is not an explicit part of the definition >of RDF, and RDF itself does not assume that a URIref identifies >something that can be retrieved." > >Fair enough, and perhaps this is all the RDF specs need to say on the >subject, but since there's a "Web" in "the Semantic Web" I'd hope that >someone, somewhere, is going to say more about this (TAG?). > > > >Summary: > >I really like this. It's quite a dense document and I'll be reading it >again to see if there's anything I've missed (third time lucky?); >thumbs-up to publish. > > > >-- >jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/ >Tel +44(0)117 9287088 Fax +44 (0)117 9287112 http://ioctl.org/jan/ >Goth isn't dead, it's just lying very still and sucking its cheeks in.
Received on Tuesday, 14 January 2003 14:17:26 UTC