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RE: References to "application profiles"

From: Karen Coyle <kcoyle@kcoyle.net>
Date: Thu, 25 Aug 2011 15:53:20 -0700
Message-ID: <20110825155320.20123dvrtd9nfbds@kcoyle.net>
To: public-xg-lld@w3.org
Quoting "Young,Jeff (OR)" <jyoung@oclc.org>:


> I'm uncomfortable using the term AP even for situations where a variety
> of existing classes and properties are getting reused. An OWL ontology
> can be created to document this situation, even if no new terms are
> being defined there.

I agree with Jeff here. It seems that AP is being used for any  
ontology that uses a mix of namespaces or that adopts properties from  
existing namespaces. This seems to me to be normal practice for  
ontology development. At what point does a choice of properties become  
an AP? In DC terms, I think that it becomes an AP only when  
constraints are added (mandatory, optional, repeatable or not, etc.).

I commonly hear people use the term AP when someone consciously  
creates a personalized or modified version of a known metadata schema.  
So a sub-set of, say, MARC that selects out the fields needed to  
encode music resources but not cartographic resources would be an AP  
in this definition.

Basically, I think we don't have a clear enough definition of AP to  
use the term in this report without going through a lengthy discussion  
that would allow us to make it clear. I'd prefer to leave it out, but  
think that the concept is important and definitely needs more thought.

kc

> Granted, you don't see much of that happening yet,
> but presumably that's presumably because people are still trying to wrap
> their minds around OWL in general.
>
>> But there are many situations in which re-using a
>> vocabulary comes with risks/costs that could motivate coining one's
> own
>> "duplicate" elements. Consider what schema.org did: they just prefered
>> to coin all the elements they need, rather than spend time shopping
>> around for existing elements--which may be not well maintained anyway.
>> That's maybe not the best practice around, but that will continue to
>> happen. In such cases, establishing alignments between element sets is
>> a lesser evil.
>
> As a species, I think we are still beginners in terms of modular
> thinking. I can't think of a single existing model or set of models that
> doesn't make me squirm and shake. "Alignments" or "mappings" give me
> hope that we will be able to adapt regardless.
>
>>
>> The "gradient" of best practice here would be: (1) own duplicate
>> element sets with no alignment; (2) own element sets with alignment to
>> existing vocabularies (3) "true" APs with re-use of existing
>> vocabularies.
>
> I agree with these idealized gradients with a couple of caveats.
>
> 1) Existing vocabularies that don't conform to best practice recipes
> suck: http://www.w3.org/TR/swbp-vocab-pub/
> 2) Some existing vocabularies (even popular ones) can be very weird and
> arguably would be better off being mapped
> 3) The ability to transform domain-specific vocabularies into foreign
> vocabularies shouldn't be that far off if the mappings exist
>
>>
>> I'm not saying that it was clearly worded here, far from it :-)
>> I can also live with this point being mentioned in another section.
> But
>> I wanted to warn against making this disappear, altogether.
>
> I suspect that all these thoughts are too controversial to used on short
> notice, though.
>
> Jeff
>
>>
>> Cheers,
>>
>> Antoine
>>
>> > Dear all,
>> >
>> > Re-reading the paragraph in [1]:
>> >
>> >      A similar concern can be voiced regarding metadata element
> sets.
>> As
>> >      testified in the Linked Open Vocabularies inventory,
>> practitioners
>> >      generally follow the good practice of re-using existing element
>> sets or
>> >      building "application profiles" of them. And some projects,
> such
>> as the
>> >      Vocabulary Mapping Framework, aim at supporting that process.
>> But the lack
>> >      of long-term support for them threatens their enduring meaning
>> and common
>> >      understanding. Further, some reference frameworks, notably
> FRBR,
>> have been
>> >      implemented in different RDF vocabularies, which are not always
>> connected
>> >      together. Such situation lowers the semantic interoperability
> of
>> the
>> >      datasets expressed using these RDF vocabularies. The community
>> should
>> >      encourage the coordinated re-use of element sets for particular
>> entity
>> >      descriptions, their extension through, e.g., application
>> profiles, or their
>> >      alignment using, e.g., semantic relations from RDFS and OWL.
>> Here, we hope
>> >      that better communication between the creators and maintainers
>> of these
>> >      resources, as encouraged by our own incubator group or the LOD-
>> LAM
>> >      initiative, will help to consolidate the conceptual connections
>> between
>> >      them.
>> >
>> > ...where "a similar concern" refers to "semantic links across value
>> vocabularies".
>> >
>> > Looking closer:
>> >
>> >> A similar concern can be voiced regarding metadata element sets. As
>> >> testified in the Linked Open Vocabularies inventory, practitioners
>> >> generally follow the good practice of re-using existing element
> sets
>> or
>> >> building "application profiles" of them.
>> >
>> > If we mean Dublin-Core-style application profiles (as Singapore
>> Framework is
>> > cited further on in the paragraph), then we could say something
> like:
>> >
>> >       A similar concern can be voiced regarding metadata element
>> sets. As
>> >       testified in the Linked Open Vocabularies inventory,
>> practitioners
>> >       generally follow the good practice of re-using existing
> element
>> sets or
>> >       building "application profiles" that re-use elements from
>> multiple sets.
>> >
>> > Then, I do not really understand the first part of this sentence:
>> >
>> >> The community should encourage the coordinated re-use of element
>> sets for
>> >> particular entity descriptions, their extension through, e.g.,
>> application
>> >> profiles, or their alignment using, e.g., semantic relations from
>> RDFS and
>> >> OWL.
>> >
>> > The phrase "encourage the coordinated re-use of element sets for
>> > particular entity descriptions" seems to be saying something like:
>> >
>> >      ...promote the use of common patterns of mixing vocabularies
> for
>> >      describing particular types of things.
>> >
>> > However, I do not think this reference to application profiles
> really
>> belongs
>> > in a section on alignment.
>> >
>> > Rather, I would like to propose the following:
>> >
>> > -- That the section "The linking issue" (vague, because the whole
> LLD
>> XG report is
>> >     arguably about a "linking issue") be renamed something like:
>> >
>> >          Semantic alignment
>> >
>> > -- In this case, the first sentence -- "Many semantic links across
>> value
>> >     vocabularies are already available..." -- could be preceded with
>> a definition
>> >     along the lines of:
>> >
>> >          "Alignments" are links between semantically equivalent,
>> similar, or
>> >          related terms or entities across different value
>> vocabularies, metadata
>> >          element sets, or datasets.
>> >
>> > -- The notion of application profiles is more appropriately
>> referenced in the point
>> >     about re-using patterns:
>> >
>> >     In the paragraph:
>> >
>> >      Design patterns allow implementers to build on the experience
> of
>> >      predecessors. Traditional cataloging practices are documented
>> with a rich
>> >      array of patterns and examples, and best practices are starting
>> to be
>> >      documented for the Linked Data space as a whole (e.g.,
>> >      <ref>http://linkeddatabook.com/editions/1.0/#htoc61</ref>). [*]
>> What is needed
>> >      are design patterns specifically tailored to LLD requirements.
>> Such design
>> >      patterns would meet the needs of people and developers who
>> understand new
>> >      techniques through patterns and examples and will increase the
>> coherence of
>> >      Library Linked Data overall.
>> >
>> >     I propose inserting a sentence:
>> >
>> >      Application profiles
> (http://dublincore.org/documents/singapore-
>> framework/)
>> >      provide a method for a community of practice to document and
>> share patterns
>> >      used for describing specific types of materials.
>> >
>> > --  ...and application profiles are also relevant to "data design"
>> [2]:
>> >
>> >      Another boost for Linked Data is the growing use of OWL for
>> purposes of
>> >      data design. Prior to OWL, domain experts could use RDFS to
>> create metadata
>> >      element sets, but there was no way to map equivalencies across
>> >      vocabularies. Among other features, OWL includes an upgrade to
>> RDFS to
>> >      support ontology mapping. This allows experts to describe their
>> domain
>> >      using community idioms, while still being interoperable with
>> related or
>> >      more common idioms. A variety of tools related to OWL can be
>> found on the
>> >      W3C's RDF wiki and OWL wiki. Unified Modeling Language (UML)
>> tools are also
>> >      value to help designers represent and manipulate domain models
>> visually.
>> >      The Ontology Definition Metamodel (ODM) specification should
>> help bridge
>> >      some of the gaps between UML and OWL. [*]
>> >
>> >     I propose to add:
>> >
>> >      Application profiles
> (http://dublincore.org/documents/singapore-
>> framework/)
>> >      provide a way to specify how a community of practice defines a
>> >      domain model and re-uses specific vocabularies in order to
>> create metadata
>> >      conforming to a particular pattern.
>> >
>> > Tom
>> >
>> > [1]
>>
> http://www.w3.org/2005/Incubator/lld/wiki/DraftReportWithTransclusion#T
>> he_linking_issue
>> > [2]
>>
> http://www.w3.org/2005/Incubator/lld/wiki/DraftReportWithTransclusion#T
>> ools_for_data_designers
>> > [3]
>>
> http://www.w3.org/2005/Incubator/lld/wiki/DraftReportWithTransclusion#D
>> evelop_and_disseminate_best-practices_design_patterns_tailored_to_LLD
>> >
>> >
>>
>>
>
>
>
>



-- 
Karen Coyle
kcoyle@kcoyle.net http://kcoyle.net
ph: 1-510-540-7596
m: 1-510-435-8234
skype: kcoylenet
Received on Thursday, 25 August 2011 22:53:49 GMT

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