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Re: References to "application profiles"

From: Antoine Isaac <aisaac@few.vu.nl>
Date: Thu, 25 Aug 2011 18:40:42 +0200
Message-ID: <4E567B0A.3020605@few.vu.nl>
To: public-xg-lld@w3.org
Hi Tom,

Thanks for the suggestions.

As far as the "linking issue" appendix is concerned, as discussed during the call, I implemented the following modifications:
http://www.w3.org/2005/Incubator/lld/wiki/index.php?title=Draft_Vocabularies_Datasets_Section2&diff=5906&oldid=5882

The remaining issue is whether we should have application profiles in one specific sentence:
  
> 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.


The point was to hint here at some "interoperability gradient". Ideally, there would be APs directly re-mixing existing classes and properties. 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.

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'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.

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#The_linking_issue
> [2] http://www.w3.org/2005/Incubator/lld/wiki/DraftReportWithTransclusion#Tools_for_data_designers
> [3] http://www.w3.org/2005/Incubator/lld/wiki/DraftReportWithTransclusion#Develop_and_disseminate_best-practices_design_patterns_tailored_to_LLD
>
>
Received on Thursday, 25 August 2011 16:39:08 GMT

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