- From: Phil Archer <phila@w3.org>
- Date: Fri, 03 Aug 2012 16:10:17 +0100
- To: Dave Reynolds <dave.e.reynolds@gmail.com>
- CC: W3C public GLD WG WG <public-gld-wg@w3.org>
Pls see below
On 28/06/2012 16:10, Dave Reynolds wrote:
> Hi Phil,
>
> Follow up from GLD call ... glancing at the ADMS document I noticed some
> oddities that are reflected in the RDF [1].
>
> Specifically, there are a number entities that look like aliases for
> skos:Concept. For example:
>
> <rdf:Description rdf:about="&skos;Concept">
> <rdfs:label xml:lang="en">Asset Type</rdfs:label>
> <rdfs:comment xml:lang="en" rdf:parseType="Literal">The
> skos:Concept class fully represents the ADMS class of Asset Type (see
> section on the <xh:a xh:href="#Code">Code</xh:a> datatype for
> details).</rdfs:comment>
> <vann:usageNote xml:lang="en">Used in ADMS to provide a
> classification of a Semantic Asset according to a controlled vocabulary,
> e.g. code list, metadata schema.</vann:usageNote>
> <rdfs:isDefinedBy rdf:resource="&skosDoc;" />
> <dcterms:identifier>skos:Concept</dcterms:identifier>
> </rdf:Description>
>
> With similar declarations for: "Code", "Interoperability Level",
> "Representation Technique" and "Status".
>
> I suspect this is a slip and that the intention was to introduce actual
> classes which would be sub-class (or equivalent-class) to skos:Concept.
>
> [If it's not a slip then this is a modelling style which I would prefer
> us to avoid. It means that we are assigning alternative labels to
> skos:Concept itself - which is problematic both technically and socially.]
Thanks Dave,
It's taken me too long to get to this but, well, I have now.
It's a slip and it's not a slip - more of a compromise I'm very happy to
change because I don't like it for all the reasons you give.
I raised the issue back in November [1] (actually, I swear I've raised
it more than once. I remember getting a reply from someone at Top
Quadrant I hadn't heard of but I can't find it). The basic problem is
that we're defining a vocabulary that uses other people's terms but that
doesn't mean we don't have something to say about them.
What I want to say here is: the way to encode the ADMS Asset Type is to
use a skos:Concept. In his reply to my question, Jeremy said I could use
sub properties/classes. Well, yes, I know that, but I really don't want
to - I want to say *use skos:Concept*. JJC then said that if people
didn't like whatever new labels were added, they didn't have to use
them, which is true of course. The e-mail I can't find from another TQ
person made the same point, i.e. you can say what you like and other
people decide whether to take any notice. With this in mind I was
slightly more ready to add new labels to existing classes although in my
sign off from that thread [2] I expressed exactly the worry as you end
with in almost the same terms ("...DCAT includes lots of Dublin Core
elements so I'm anxious to do this in a way that is semantically and
socially right.")
But, if it is not right to add new labels to existing terms - and I
agree entirely, I don't think it is - how can we proceed? I haven't
updated the schema in w3.org space yet but I have prepared a version
that I hope is better in this regard - although it still doesn't feel
right [3]. The key bit is:
<http://www.w3.org/2004/02/skos/core#Concept>
rdfs:label "Concept"@en ;
rdfs:comment """The skos:Concept class fully represents the following
ADMS classes:
- Asset Type
- Code
- Interoperability Level
- Representation Technique
- Status
In each case, the use of a Concept from a suitable Concept Scheme will
provide a suitable value from a controlled vocabulary. In the particular
case of the ADMS data type of Code, the intention is that the
skos:Concept class be used as follows:
- for the content property, use skos:notation
- the ADMS list property will be taken care of by means of the
skos:inScheme property;
- the list agency property is likely to be applied to the scheme as a
whole for which dcterms:creator is appropriate;
- the list version property can be fulfilled using schema:version.""" ;
rdfs:isDefinedBy <http://www.w3.org/TR/skos-reference/> ;
dcterms:identifier skos:Concept .
Is that a better way of re-using an existing term in a new,
formally-defined vocabulary?
Phil.
[1] http://lists.w3.org/Archives/Public/semantic-web/2011Nov/0150.html
[2] http://lists.w3.org/Archives/Public/semantic-web/2011Dec/0003.html
[3] http://philarcher.org/isa/adms20120731.rdf
>
> [1] http://www.w3.org/ns/adms.rdf
>
>
--
Phil Archer
W3C eGovernment
http://www.w3.org/egov/
http://philarcher.org
+44 (0)7887 767755
@philarcher1
Received on Friday, 3 August 2012 15:10:47 UTC