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Re: RDA and ranges

From: Karen Coyle <kcoyle@kcoyle.net>
Date: Wed, 18 Aug 2010 08:10:52 -0700
Message-ID: <20100818081052.b8fx8sr528c8c8sc@kcoyle.net>
To: Emmanuelle Bermes <manue.fig@gmail.com>
Cc: public-lld@w3.org
Quoting Emmanuelle Bermes <manue.fig@gmail.com>:

> In your diagram, I see no middle-term between defining a very precise range,
> and no range at all.

Right. That's where I got stuck, myself.


  However, it could be useful to determine at least if
> the range should be a literal, or a resource with a URI.

Exactly. And somewhere in the text of RDA we should be able to  
discover that, although it's often not clear. It's not clear because  
most sections of RDA have a number of "if" "else" and other options.


>
> When you state that the range for rdavocab:titleProper(Manifestation) is
> "RDA 2.3.2", what you actually mean is that the range is a literal, and the
> literal should be constructed by the cataloguer following RDA rules 2.3.2.
> This is something that cannot be checked by a machine, and we have to
> remember that ontology semantics is meant for machine interpretation.


Yes, you are right. The cataloguing rule itself isn't going to be  
something that can be validated. However, I can assure you that it is  
the intention of the RDA developers that the elements they have  
defined are only to be used following the rules that, in a sense,  
"spawned" the elements. So perhaps what would be more correct would be  
to add the rule number into the definition, and derive the range from  
what we can understand from the guidance text. (Not an easy job, btw).  
However, there must be a distinction between a titleProper created  
following the RDA guidance rules and, as an example, a titleProper  
created following the AACR2 guidance rules. These are different  
properties. I realize that not all communities approach metadata at  
this level of specificity, but ... well, welcome to my world. :-) For  
those of us who lived through the change in name forms between AACR  
and AACR2, we know that rule changes can actually mean the creation of  
different/incompatible data for what may appear to be "the same thing."

This still leaves us with the question of how do we generalize RDA?  
And my idea is still that the big difference between general and not  
general is not limited to the RDA vocabularies' binding with FRBR, but  
also its binding with the rules themselves. So this is in response to  
the treatment of the FRBR binding as being overly ontologically strict  
(as Tom described it). I agree with Ross that the FRBR binding could  
more easily be handled like:

_:a
   rdvocab:titleProper "A proper title"@en;
   rdf:type frbr:Manifestation.

And that seems to me to be a logical role for an application profile.  
(Something we tried desperately to convince the JSC to accept, but  
that approach was rejected.)

I am saying that we now have yet another "facet," which is whether the  
data has been created following the RDA guidance rules. This, too,  
could be expressed in an application profile. However, if we do not  
use APs, then we have yet another duplication of every RDA property:  
uses RDA rules/other. (Either doesn't use the rules or is unknown.)

I admit that this is a mess, and maybe I shouldn't have brought it up,  
but it doesn't make sense to me to discuss RDA properties'  
relationship to FRBR while ignoring the relationship to the guidance  
rules.

Diane will kill me for this (because it would mean a huge amount of  
work on the registry) but I have often thought that the generalized  
terms should be placed under a different URI (and didn't Gordon say  
recently that that had been discussed in the JSC?), and those would  
implicitly be separate from the RDA rules. We shouldn't call those  
generalized terms "RDA" any more than we would give the MARC elements  
a URI that implies that they are derived from AACR2.

Now I think I have to create a new diagram. :-)

kc

> Even in current library systems, the adequacy of the content of metadata
> fields to cataloguing rules is not checked by machines. It is checked in a
> quality assessment process by humans (at least, in my library - well if
> someone knows how to check that in an automated way, please send me an
> e-mail ;-). This adequacy relies on guidelines and training of cataloguers,
> and not on a formal metadata structure (be it MARC, MARCXML, MODS, DC or any
> other).
>
> So, to go back to the model, here is how I see things could be done :
> - rdavocab:titleProper(Manifestation) would be declared as a property with
> "literal" as range
> - in the note or description, it would be stated that the literal is
> expected to be constructed according to RDA rule 2.3.2.
> I have to dive deeper into application profiles to see how they can help
> with expressing this constraint in a more explicit or formal way.
>
> Then the "super-properties" (in your example rdavocab:titleProper and
> rdavocab:title) could be declared with only "litteral" as a range and no
> precision on how the litteral should be constructed. That would make them
> sub-properties of DC:title, which has no range. Maybe they could have at
> least "FRBR group 1 entity" (WEMI) as a domain (well, that's another
> discussion).
> Or even, if they have no domain and no range, I don't see a reason why they
> couldn't be declared equivalent to DC:title (rather than subproperties).
> I guess it was the point made by Dan, but I must admit there are some things
> that are not completely clear to me in his comment.
>
> Obviously, the range discussion is completely different when the range is
> not a literal but a class or a resource.
>
> Emmanuelle
>
> On Wed, Aug 18, 2010 at 9:01 AM, Dan Brickley <danbri@danbri.org> wrote:
>
>> On Wed, Aug 18, 2010 at 2:09 AM, Karen Coyle <kcoyle@kcoyle.net> wrote:
>> > There's been something tickling my brain for a bit, so I sat down to try
>> to
>> > draw up a diagram. Essentially, the question is: what is the domain &
>> range
>> > of an RDA property? Then I began to wonder what is the domain and range
>> of a
>> > property based on RDA but not bound to a FRBR domain?
>> >
>> > My unfinished diagram is here:
>> >
>> > kcoyle.net/domainsranges.pdf
>> >
>> > and I now realize that title isn't the best example to use. But the key
>> > element, in my mind, is that the RDA guidance rules both guide the
>> metadata
>> > creator and define the range of the element. Those ranges are inherent in
>> > the rules but have not been extracted into the registry, in part because
>> > many of the ranges are quite complex. In the rules you find how the
>> property
>> > is to be structured and what values are valid, which to me is the
>> definition
>> > of the range.
>> >
>> > Note that in the diagram I have only filled in the domain and range at
>> the
>> > bottom (most specific) level. That is because I'm not sure what to do
>> beyond
>> > that. If we treat the RDA rules as describing the ranges for the
>> properties,
>> > then all of the properties, regardless of whether they are bound to FRBR,
>> > are very tightly defined (probably what Tom would call ontologically
>> > strict). If we wish for other communities to provide guidance rules of
>> their
>> > own for the properties, then it becomes hard to think of them as RDA
>> > properties. (This is a can of worms that has been a matter of discussion
>> > between JSC and the registry.)
>> >
>> > What I am getting at is that we may need a hierarchy that goes like this
>> > (from most specific to most general):
>> >
>> > 1. RDA + FRBR -- range is as defined in RDA; domain is FRBR entity
>> > 2. RDA alone -- range is as defined in RDA; no domain?
>> > 3. Property with definition -- range and domain are open
>> >
>> > I hope I've made some sense here. Although we've discussed whether RDA
>> > properties must be bound to FRBR, in fact I think that RDA's definition
>> of
>> > the values/ranges is more of a constraint than FRBR.
>>
>> This is a useful exercise!
>>
>> Quick question. Going from the diagram alone, it isn't clear to me
>> exactly how dcterms:title is more general than rdvocab:title.
>>
>> * dcterms:title, definition: A name given to the resource.
>> * rdvocab:title, definition: A word, character, or group of words
>> and/or characters that names a resource or a work contained in it.
>>
>> >From those definitions alone, it seems that rdvocab:title allows some
>> cases that aren't anticipated by dcterms:title, namely when the value
>> is a name for a work contained within the main thing we're describing.
>>
>> I read "a word, character, or group of words and/or characters" as
>> approximating the concept of "text", although on a strict reading, it
>> seems a little confused as to whether the group of words/characters is
>> necessarily ordered. Presumably the ordered group of characters [ "H",
>> "a", "m", "l", "t", "e" ] isn't a name given to Shakespeare's Hamlet,
>> whereas the ordered group  [ "H", "a", "m", "l", "e", "t" ] is?
>>
>> If we proceed with this level of nitpicking it'll take forever; is it
>> OK to assume "text that" when I see "A word, character, or group of
>> words and/or characters that"? In which case, next question is whether
>> the text can be a separate entity/resource/thing rather what RDF would
>> call a literal. If 'yes', I can't see anything that would be a value
>> fitting the dcterms:title definition but fails to match rdvocab:title;
>> if 'no', it seems the properties as defined have only partial overlap
>> rather than forming a hierarchy.
>>
>> All that said, your main point seems to be around the RD vocab and
>> FRBR, perhaps the DC aspect is a distraction?
>>
>> cheers,
>>
>> Dan
>>
>>
>> > kc
>> >
>> > p.s. I will try to locate some better examples of RDA rules as ranges.
>> >
>> > --
>> > Karen Coyle
>> > kcoyle@kcoyle.net http://kcoyle.net
>> > ph: 1-510-540-7596
>> > m: 1-510-435-8234
>> > skype: kcoylenet
>> >
>> >
>> >
>>
>>
>



-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
ph: 1-510-540-7596
m: 1-510-435-8234
skype: kcoylenet
Received on Wednesday, 18 August 2010 15:11:27 UTC

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