- From: Antoine Isaac <aisaac@few.vu.nl>
- Date: Thu, 25 Aug 2011 18:40:42 +0200
- 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 UTC