Re: License unknown

Hi Alasdair,

It is good practice in my opinion to not state unknown facts. If you
want to state there should be a license but you don't know it I think
some owl modelling is called for.

e.g. roughly like this.

dusty_data a dct:Dataset .
dusty_data rdfs:subClassOf [ a owl:Restriction ;
                                            owl:onProperty dct:license ;
                                            owl:minCardinality 1 ]


If anyone does something like

dusty_data a dct:dataset .
dusty_data dct:license bad_example:unknown_license .

and then someone figures out it has a license .

dusty_data a dct:Dataset .
dusty_data dct:license cc:zero .

And puts all those triples into one store/ontology then queries will
start to return wrong data.

SELECT ?datasetWithALicense
WHERE {
?datasetWithALicense dct:license ?license .
}

Will give 2 bindings for ?dataset and ?license one of them being wrong now.

If you ask the same question depending on the better modelling then
you get the correct answer in both cases.

SELECT ?datasetWIthoutLicense
WHERE {
?datasetWIthoutLicense a dct;Dataset .
MINUS ( ?datasetWIthoutLicense dct:license ?license )
}

SELECT ?datasetWIthALicense
WHERE {
?datasetWIthALicense a dct;Dataset .
?datasetWIthALicense dct:license ?license .
}

Both give the expected results.


In general in RDF just state what you know and describe what you don't know.

Regards,
Jerven

On Mon, Jun 2, 2014 at 5:25 PM, Gray, Alasdair J G <A.J.G.Gray@hw.ac.uk> wrote:
> Hi,
>
> I am working to help shape the Healthcare and Life Sciences community
> profile for describing datasets, current version available from [1]
>
> One of our goals is that there is a minimal set of properties that are
> available for all datasets, and we would like these properties to include
> the license. However we have the problem that for several legacy datasets
> the license is simply unknown. Does anyone know of a resource that can be
> used to represent that the license is unknown as the value of a
> dcterms:license predicate?
>
> Thanks
>
> Alasdair
>
> [1] https://github.com/joejimbo/HCLSDatasetDescriptions
>
> Alasdair J G Gray
> Lecturer in Computer Science, Heriot-Watt University, UK.
> Email: A.J.G.Gray@hw.ac.uk
> Web: MailScanner has detected a possible fraud attempt from
> "www.macs.hw.ac.uk" claiming to be http://www.alasdairjggray.co.uk
> ORCID: http://orcid.org/0000-0002-5711-4872
> Telephone: +44 131 451 3429
> Twitter: @gray_alasdair
>
>
>
>
>
>
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-- 
Jerven Bolleman
me@jerven.eu

Received on Monday, 2 June 2014 15:47:44 UTC