Yves Raimond wrote:
>> Ontology modularization is
>> a pretty difficult task, and people use various heuristics for deciding what
>> to put in the subset being served for an element. There is no guarantee that
>> the fragment you get contains everything that you need.
>>
>>
>
> Sorry, just jumping on that, as this is something I am having quite a
> lot of troubles to understand (and since quite a long time). Maybe I
> am missing something obvious, but how does using owl:imports avoid
> this randomness? When using it, you're still hoping that dereferencing
> the object of owl:imports will get you the relevant information? I
> agree that owl:imports allows you to commit to a whole ontology
> instead of committing to single terms within an ontology, but I would
> argue that in most cases, you just want to pick a few terms in an
> ontology.
There is no safe way of importing only parts of an ontology, unless you
know that its modularization is 100% reliable.
Serving fragments of likely relevant parts of an ontology for reducing
the network overhead is not the same as proper modularization of the
ontology.
Thus, you should import the ontology only, and not the fragments served
via the dereferencable IDs of selected ontology elements. Partial
commitment would require that there is a proper definition of the part.
> For example, I may agree with the way OWL-Time models
> time-zones etc., but I don't agree with the way it models time
> intervals vs. events.
>
>
If that ontology has two explicit parts, e.g. time-core and time-full,
then you can commit to each one individually. If not, I would strongly
discourage committing to a random fragment only.
Cheers
Martin
--
--------------------------------------------------------------
martin hepp
e-business & web science research group
universitaet der bundeswehr muenchen
e-mail: mhepp@computer.org
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Check out the GoodRelations vocabulary for E-Commerce on the Web of Data!
========================================================================
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