[tdwg-content] assertions in DwC terms

[Hilmar Lapp]

On Jun 5, 2009, at 9:20 PM, John R. WIECZOREK wrote:

> [...] The first s organization of the standard. The domains help  
> organize the properties in ways that help people to understand their  
> meaning and purpose.

That's a worthwhile goal but isn't that using the wrong means? I.e.,  
specifying the domain is telling something - and in an unambiguous  
manner - to machines, not humans.

You can of course create user interfaces or renderings that turns the  
domain specification into something meaningful to humans, too. But you  
could use any term property for that, couldn't you? I.e., you could  
use a property that doesn't imply specific and possibly far reaching  
machine inferences. (I haven't had time to check yet but I suspect  
that there are - W3C or not - conventions for how to add human- 
targeted class and property annotations to vocabularies.)

(BTW for comparison purposes, note that DC doesn't assert any domain  
or range for any of its terms, allowing the broadest possible use.)

> [...] The second reason for the domain assignments is that we lack a  
> formal ontology, and this is an attempt to have one to govern at  
> least the terms within this standard.

I'd argue that it's worth distinguishing between a metadata vocabulary  
and a formal ontology, and that having one product try to be both may  
limit its ability to fully satisfy both.

A standard metadata vocabulary with the primary purpose that we all  
call the same thing by the same name is broadly useful and can help  
enormously with data integration across fields as diverse as genetics,  
genomics, systematics, ecology, and taxonomy (and more, as we heard in  
London). A formal ontology that supports inferences over integrated  
data is also highly useful, but not necessarily at the same breadth.

> What is the potentially problematic future case of asserting that a
> specimen is an dwcterms:Occurrence? It is one.

My example was indeed a weak one, as we are indeed referencing  
specimens. For example, I couldn't use dwcterms:collectionCode to  
assert a code for a museum collection, because it would imply that the  
collection is an dwcterms:Occurrence.

Maybe you don't want people to use DwCTerms for anything else other  
than describing specimen records, but I'd argue that without such  
limitations the standard could become much more broadly useful.

As a comparison, dc:creator and dc:title are meanwhile being used in  
vastly more contexts than the original authors of DC had probably  
imagined. I'm not sure this would have also happened if applying  
dc:title implied specific assertions about the nature of what it is  
being applied to.

Just my $0.02.

	-hilmar

-- 
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: Hilmar Lapp  -:-  Durham, NC  -:- hlapp at duke dot edu :
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