Comments inline.
On Sun, Oct 25, 2009 at 11:50 AM, Gregor Hagedorn g.m.hagedorn@gmail.com wrote:
2009/10/25 John R. WIECZOREK tuco@berkeley.edu:
Can you explain the difference between your new term dwc:subtype and the term dwc:basisOfRecord most recently proposed in this thread?
I see no difference bewteen your dwc:subtype and the proposed dwc:basisOfRecord except the name. The term basisOfRecord has been used for this purpose in Darwin Core since 13 Jun 2003. I think precedence should prevail.
Please see my slight preference for the word "subtype" over "basisOfRecord" as a secondary question.
The essence is that I propose to use DublinCore (precendence since 1995 and extremely widely adapted) where it applies.
Agreed.
basisOfRecord is a mixture of DublinCore type terms, and subtypes of DublinCore terms. In the latter case DwC omits the applicable DublinCore resource type vocabulary.
I think you missed some messages in the thread. What you say above is true of the Darwin Core as published (basisOfRecord has StillImage, MovingImage, and Sound among the recommendations), but I proposed a solution (24 Oct 11:29AM) in which there is no mixing. What is "the latter case" to which you refer - subtypes of Dublin Core terms defined by Darwin Core? If so, you're correct, Darwin Core recommends a vocabulary of literals, not refinements of Dublin Core Type vocabulary (see my commentary in this thread 24 Oct 11:57PM, beginning with "The following may be confusing...").
Thus any DC-aware consumer of the data has to do both a mapping of dwc:StillImage to http://purl.org/dc/dcmitype/StillImage and imply that the resource quoted throuh PreservedSpecimen, FossilSpecimen, LivingSpecimen is a http://purl.org/dc/dcmitype/PhysicalObject, that a HumanObservation or MachineObservation must be http://purl.org/dc/dcmitype/Event, and NomenclaturalChecklist a http://purl.org/dc/dcmitype/Text.
Again, there would be no dwc:StillImage. Instead dcmitype:StillImage would be a possible value for dcterms:type. There would be no formal declaration of the string literal vocabulary of basisOfRecord, and no refinements of DCMI Type vocabulary for them.
I really think the answer (well, my answer) to your concerns is in that paragraph about "The following may be confusing...", which I'll repeat here for convenience. If I haven't understood your concern, please let me know. If you think I did understand it but you don't like my response (encapsulated below), please propose an alternative.
Thanks,
John
JOHN R WIECZOREK wrote (24 Oct 2009 11:57PM):
"The following may be confusing and isn't necessary to the resolution of the issue mentioned, but I thought I'd bring it up for the sake of completeness. Continue at your own risk. The DublinCore type vocabulary (Image, StillImage, MovingImage, etc.) is composed of classes, not properties, and some of the classes are subtypes of others (for example, StillImage and MovingImage have the subClassOf attribute rdfs:subClassOf rdf:resource="http://purl.org/dc/dcmitype/Image"/). One could create formal vocabulary terms under the Darwin Core type vocabulary for dwctype:PreservedSpecimen, dwctype:FossilSpecimen, dwctype:LivingSpecimen as subclasses of dcmitype:PhysicalObject (rdfs:subClassOf rdf:resource="http://purl.org/dc/dcmitype/PhysicalObject"/), for dwctype:HumanObservation and dwctype:MachineObservation as subclasses of dcmitype:Event (rdfs:subClassOf rdf:resource="http://purl.org/dc/dcmitype/Event"/), and for the remaining terms (TaxonDistribution,TaxonName, NomenclaturalAct, and TaxonNameUsage) as entirely new classes. This was actually done in a previous iteration of the Darwin Core before public review. These new classes (the new vocabulary terms) could be used as values of dcterms:type (in XML, for example, by declaring dcterms:type xsi:type=”dwc:DwCType”) and a basisOfRecord term wouldn't be needed. This is what I mean by a formal vocabulary. In the Darwin Core as published this option was abandoned as being too much of a maintenance burden even within our community, as there is a tendency to split and lump and split ad infinitum. Precedent for not taking on more than can be reasonably handled by volunteer labor can be found in Thomas Baker's "Maintaining a vocabulary: Practices, policies, and models around Dublin Core" (http://dcpapers.dublincore.org/ojs/pubs/article/viewFile/765/761), in which the tendency toward simplicity is defended. In face of this challenge it was deemed prudent to use an informal recommended controlled vocabulary for basisOfRecord that could be managed without affecting the standard, and therefore without incurring the process overhead every time someone wants to add new capabilities using Darwin Core. Time will tell us if this was the right course, but for now, it is what we all ratified by not saying anything to the contrary."
Gregor
Gregor wrote:
Thus, while I think recordType is a DarwinCore categorization of intent, not resource, and is fine, I still feel that the basisOfRecord vocabulary is a subtyping of resource types.
I therefore believe that it would make life simpler for many consumers of DwC if DwC would adopt DublinCore type for its own purposes. Instead of having basisOfRecord = PreservedSpecimen FossilSpecimen LivingSpecimen HumanObservation MachineObservation StillImage MovingImage Sound NomenclaturalChecklist
DarwinCore would first use the DublinCore vocabulary: dcterms:type= StillImage MovingImage Sound Event PhysicalObject /ADDED, forgotten in previous mail Text
and then use dwc:subtype= PreservedSpecimen FossilSpecimen LivingSpecimen HumanObservation MachineObservation NomenclaturalChecklist
for those subtypes of dcterms:type that DarwinCore cares about to specify further. This would allow consumers to directly map DwC records into their DublinCore metadata, rather than analysing the implied hierarchy and mapping in the flattened basisOfRecord.