It is interesting that Jonathan Reese sees the semantic web and the LOD cloud in a different way that Tim Berners-Lee.

The issue with LOD semantics is being worked out on the public-lod list.

With the exception of some of the LOD services that do inferencing on cloud data, all inferencing is currently done on one machine with all the relevant data loaded.

If you don't like SKOS or some other problematic ontology entailment you can simply:

1) Use a modified version of SKOS for your own inferencing.

Also it would be interesting to see some real world inferencing using a data set markup in the current DarwinCore that demonstrates:

1) That it works 2) That it works in a useful way

So in addition to failing to work within the standards of the larger informatics community TDWG*, is failing to demonstrate that it has a working, useful standard.

Pointing out potential problems with SKOS etc. does not demonstrate that you have anything better.

If the opinions of the real experts in the semantic web community matter then you might want to consider what they think of my work.

Respectfully,

- Pete

* It is welcome news to me that TDWG is now going to follow the advice of the semantic web community

On Mon, Nov 15, 2010 at 11:29 AM, Bob Morris morris.bob@gmail.com wrote:

Jonathan Reese, an employee of the Science Commons and TDWG member (and who knows way more about semantic web than I do) recently sent me this. I copy it here with his permission. Each of the paragraphs seems to me to be germane in different ways to the discussions about what should be an Individual. For those not deep into RDF, for the word "axiom", you could loosely understand "rule", although that term also has technical meaning that is sometimes a little different. Jonathan raises an important use case in the second paragraph, which is data quality control. That's a topic of interest to many, but especially those following the new Annotation Interest Group. Originally, this was part of a discussion we had about my favorite hobby horse, rdfs:domain. He is not on my side. When people who know more than I do about something are skeptical of my arguments about it, I usually suspend disbelief and temporarily adopt their position.

Jonathan's first point is pretty much what Paul Murray observed yesterday in response to a question of Kevin Richards.

"(a) subclassing is the way in RDFS or OWL you would connect the more specific to the less specific, so that you can apply general theorems to a more specific entity. That is, a well-documented data set would be rendered using classes and properties that were very specific so as to not lose information, and then could be merged with a badly-documented data set by relaxing to more general classes and properties using subclass and subproperty knowledge.

(b) axioms (i.e. specificity) are valuable not only for expressing operational and inferential semantics, but also for "sanity checking" e.g. consistency, satisfiability, Clark/Parsia integrity checks ( http://clarkparsia.com/pellet/icv/ ), and similar. Being able to detect ill-formed inputs is incredibly valuable.

People talk past one another because there are many distinct use cases for RDF and assumptions are rarely surfaced. For L(O)D, you're interested in making lots of links with little effort. Semantics is the enemy because it drives up costs. For semantic web, on the other hand, you're interested in semantics, i.e. understanding and documenting the import of what's asserted and making a best effort to only assert things that are true, even in the presence of open world assumption and data set extensibility. Semantics is expensive because it requires real thought and often a lot of reverse engineering. People coming from these two places will never be able to get along."

---Jonathan Rees in email to Bob Morris

Bob Morris

-- Robert A. Morris Emeritus Professor of Computer Science UMASS-Boston 100 Morrissey Blvd Boston, MA 02125-3390 Associate, Harvard University Herbaria email: morris.bob@gmail.com web: http://bdei.cs.umb.edu/ web: http://etaxonomy.org/mw/FilteredPush http://www.cs.umb.edu/~ram phone (+1) 857 222 7992 (mobile) _______________________________________________ tdwg-tag mailing list tdwg-tag@lists.tdwg.org http://lists.tdwg.org/mailman/listinfo/tdwg-tag