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From: DCMI Architecture Group [mailto:DC-ARCHITECTURE@JISCMAIL.AC.UK]
On Behalf Of Andy Powell
Sent: Thursday, March 23, 2006 5:21 PM
To: DC-ARCHITECTURE@JISCMAIL.AC.UK
Subject: [DC-ARCHITECTURE] FW: Domains and ranges of DC properties
This topic was discussed briefly at the f2f meeting in Madrid - and has
trundled on slowly behind the scenes since then, as part of the DC-RDF
Taskforce activity.
The proposed list of domain and range classes are in the DC-Architecture
wiki at
http://dublincore.org/architecturewiki/DCPropertyDomainsRanges
Given that this discussion is largely about semantics, we agreed at
todays Usage Board teleconf, that discussion about this list would move
into the remit of the UB. However, that doesn't mean that we aren't
interested in people's views. So, if you have comments on the above
document, please share them here.
(As an aside, we're going to attempt to bring back DC-RDF Taskforce
discussion onto the main list - since the current use of a sub-list
seems to have fragmented some our conversations!).
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Date: Tue, 28 Mar 2006 15:53:26 +0100
From: Ann Apps <ann.apps@MANCHESTER.AC.UK>
Organization: University of Manchester
Subject: Re: FW: Domains and ranges of DC properties
To: DC-ARCHITECTURE@JISCMAIL.AC.UK
Andy, and All,
A few comments after a very quick scan of this list.
Location: Is this just physical and geographic locations? If so maybe it sh
ould be more explicit, ie define 'place'. Or does is include machine/intern
et location?
RightsStatement: I think one may also want to make a rights statement about
a Service. But Service is defined as being of Agent class (which I have so
me reservations about), and so outside the scope of a rightsStatement.
Topic: I think 'subject' also needs defining. I assume it means 'keyword' o
r classification as in dc:subject. But the word 'subject' has other meaning
s, eg the 'subject' of a sentence, or a 'subject of the Queen'.
I assume that 'DigitalResource' can include Service, and that 'PhysicalReso
urce' includes Person - the definitions seem to allow that. So I could have
a Collection of Services or a Collection of Persons.
Being really picky - can an animal be an Agent? Or does Agent imply some in
telligence or resource creation?
Should the list include 'event'? Or is that covered by ConceptualResource?
And a 'Class' is the 'class of all classes'... Right...
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Date: Tue, 28 Mar 2006 17:33:31 +0100
Sender: DCMI Architecture Group <DC-ARCHITECTURE@JISCMAIL.AC.UK>
From: Pete Johnston <p.johnston@UKOLN.AC.UK>
Subject: Re: FW: Domains and ranges of DC properties
To: DC-ARCHITECTURE@JISCMAIL.AC.UK
Ann Apps wrote:
> Topic: I think 'subject' also needs defining. I assume it
> means 'keyword' or classification as in dc:subject. But the
> word 'subject' has other meanings, eg the 'subject' of a
> sentence, or a 'subject of the Queen'.
I guess I find the "Topic" class a bit problematic too. What is a
"Topic"? I can understand the notion of a relationship/property
capturing the notion that resource:y is a topic of resource:x
resource:x has-topic resource:y
That's what the dc:subject property does. But I'm not really clear what
the class of "Topics" is - apart from the class of things which might be
values of dc:subject! Is a Topic a "Conceptual Resource"? Or is the
Topic class broader?
What _is_ the range of dc:subject? Can a person be the value of
dc:subject? A place? An event? Certainly I can have a book which has as
its topic Che Guevara (person) or the Sierra Maestra (place) or the
Cuban Revolution (event). If all these things can be values for
dc:subject, I think a resource of any type can be a value of dc:subject,
and the range of dc:subject is just the class Resource.
If on the other hand we are saying that the value of dc:subject is
always a "conceptual resource" - so in my examples above the values
would be "the concept of the person Che Guevara", "the concept of the
place the Sierra Maestra", "the concept of the event the Cuban
Revolution", rather than the person/place/event. There may be a
person/place/event related to the concept, but they are distinct
resources. That would be a consistent approach too, I think (even if I
find it somewhat slippery at times).
I think, the introduction of the "Topic" class is suggesting the latter
approach, but I'm not sure, and I think it needs clarification. And if
it is the case then I think maybe the range of dc:subject is just the
class of Conceptual Resources, not some separate class of Topics.
> And a 'Class' is the 'class of all classes'... Right...
Those phrases are all intended to be descriptions/definitions of
classes, so it's not saying 'a Class is....'. Rather, it's saying 'the
class labelled "Class" (in practice it would have a URI) is'.... i.e.
that class is the class of all classes, or the class of resources which
are classes. It does make sense, I think.
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Date: Thu, 23 Mar 2006 17:12:47 -0000
From: Andy Powell <andy.powell@EDUSERV.ORG.UK>
Subject: Domains and ranges
To: DC-USAGE@JISCMAIL.AC.UK
As discussed in today's call, I've re-worked the list of domains and
ranges to remove the use of the FRBR-like Item, Work and Manifestation.
Instead, I just use Resource, PhysicalResource and DigitalResource.
(Yes, the definitions of the latter two need some work!).
I suspect that I mainly added the FRBR stuff to cope with the use of
'item' in the 'collection description' properties. As redefined, you
can't have a collection of concepts or a collection of people, only a
collection of PhysicalResources or a collection of DigitalResources.
I think that is probably what is inteded by the DC-CD WG, but I might be
wrong.
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Date: Thu, 23 Mar 2006 17:42:26 +0000
From: Pete Johnston <p.johnston@UKOLN.AC.UK>
Subject: Re: Domains and ranges
To: DC-USAGE@JISCMAIL.AC.UK
Andy Powell wrote:
> I suspect that I mainly added the FRBR stuff to cope with the use of
> 'item' in the 'collection description' properties. As redefined, you
> can't have a collection of concepts or a collection of people, only a
> collection of PhysicalResources or a collection of DigitalResources.
>
> I think that is probably what is inteded by the DC-CD WG, but I might be
> wrong.
It was what I intended, based on what Mike Heaney says
====
Collection: An aggregation of physical and/or electronic Items.
====
and
====
Item: The concrete (incorporating physical and electronic) realisation
of Content.
Note: In so far as this analysis is concerned with collections, the
entities Content and Item will be considered only to the extent that
their types and attributes impinge upon Collection Description. In the
vast majority of cases, too, the Items will coincide with what FRBR
calls Items, not Manifestations. 'Item' has been chosen as the most
neutral term in preference to other terms which have been used such as
'Document' or 'Document-like Object'. 'Item' can most easily embrace all
of the concepts of physical and electronic, text and non-text, and human
and natural creations.
====
And I argued, therefore, that an aggregation of events (definitely) and
an aggregation of services (probably) were not collections as defined by
Heaney and were out of scope for the DC CD AP, and such classes should
not be part of the collection type vocabulary.
Others in the DC CD WG argued against that - I think really just on the
basis of "intuitive" notions of "collection" and/or on the basis that if
we were basing our collection classes on the DCMI Type list then we had
to take the whole list, rather than on a reading of Heaney - and (in a
moment of weakness) I caved in to the tyranny of democracy.
Though I have continued to think they were wrong and I should have stood
my ground, so I may go back and fight that out again in the WG ;-)
[1] http://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0411&L=dc-collections&P=172
[2] http://www.jiscmail.ac.uk/cgi-bin/webadmin?A2=ind0412&L=dc-collections&P=60
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Date: Thu, 23 Mar 2006 17:55:22 +0000
From: Pete Johnston <p.johnston@UKOLN.AC.UK>
Subject: Re: Domains and ranges
To: DC-USAGE@JISCMAIL.AC.UK
Andy Powell wrote:
> I suspect that I mainly added the FRBR stuff to cope with the use of
> 'item' in the 'collection description' properties. As redefined, you
> can't have a collection of concepts or a collection of people, only a
> collection of PhysicalResources or a collection of DigitalResources.
This also raises the interesting question of whether the new class
describes/defined in
http://dublincore.org/architecturewiki/DCPropertyDomainsRanges
as
Collection: The class of everything that is an aggregation of one or
more DigitalResources or PhysicalResources.
is the same as the existing class dcmitype:Collection ("A collection is
an aggregation of items. The term collection means that the resource is
described as a group; its parts may be separately described and navigated")
Or whether this new class is in fact a subclass of dcmitype:Collection.
I don't know the answer: it all depends on the definition of "item" in
the description/definition of dcmitype:Collection. ;-)
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2006-03-23 Discussion on Usage Board telecon
Diane: in looking through possible classes, I see that 3 out of
4 use FRBR -- I was trying to see where these were assigned.
Andy: I thought all these classes were used somewhere but
need to check. Some may only be used in definitions of other
classes - so not directly assigned. For example, "work" is
there in order to define "manifestation". Need to double-check
which classes are actually used. -- check to make sure there
are no "hanging classes" that do not get used anywhere.
Diane: Problems arise with FRBR expressions: often,
"manifestations" relate to expressions, not necessarily to
works. Eg, translation as an expression. Manifestation of
that translation skips a level in terms of FRBR. Difficult
to always distinguish btw manifestation and an Item; things
can be both Manifestation and Item in the digital context.
Most work on FRBR has come from a library context. Joe: in
the archival community, everything is a "copy". Resources --
digital resources and physical resources -- but we do not
necessarily need to talk about items and manifestations.
What are the consequences about being explicit about domains
and ranges? Diane: good to discuss but agree with Tom -- one
step at a time. Andy: the minimal aim - if we cannot agree
on actual classes - is to decide where this document is going.