Re: License unknown

Hi Alasdair,

I think you are closing the world the wrong way. Both in limiting a
dataset to have one license and secondly by having an "unknown" string
to encode that you don't know something.
Instead of using "unknown" you should use a blank node.

cc:CC0 owl:sameAs "unknown"

is plain wrong and can't be inferred

cc:CC0 owl:sameAs _:1

is fine and a nice way of allowing dataset from different sources
descriptions to be combined and give more information.

If you don't want a blank node, make a local node instead.
cc:CC0 owl:sameAs <./#license>

I implore you to change your mind on this. Choose semantics over special values!

Regards,
Jerven


On Mon, Jun 16, 2014 at 5:44 PM, Gray, Alasdair J G <A.J.G.Gray@hw.ac.uk> wrote:
> Hi Jerven,
>
> We are trying to ensure that a license is provided for a dataset, and that
> only one license is provided. (We are closing the world in certain areas.)
>
> Our proposed solution is written up at
> https://github.com/joejimbo/HCLSDatasetDescriptions/issues/65
>
> Alasdair
>
> On 2 Jun 2014, at 16:47, Jerven Bolleman <me@jerven.eu> wrote:
>
> 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
>
>
>
>
>
>
> ________________________________
>
> Sunday Times Scottish University of the Year 2011-2013
> Top in the UK for student experience
> Fourth university in the UK and top in Scotland (National Student Survey
> 2012)
>
> We invite research leaders and ambitious early career researchers to join us
> in leading and driving research in key inter-disciplinary themes. Please see
> www.hw.ac.uk/researchleaders for further information and how to apply.
>
> Heriot-Watt University is a Scottish charity registered under charity number
> SC000278.
>
>
>
>
> --
> Jerven Bolleman
> me@jerven.eu
>
>
> 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
>
>
>
>
>
>
> ________________________________
>
> Sunday Times Scottish University of the Year 2011-2013
> Top in the UK for student experience
> Fourth university in the UK and top in Scotland (National Student Survey
> 2012)
>
> We invite research leaders and ambitious early career researchers to join us
> in leading and driving research in key inter-disciplinary themes. Please see
> www.hw.ac.uk/researchleaders for further information and how to apply.
>
> Heriot-Watt University is a Scottish charity registered under charity number
> SC000278.



-- 
Jerven Bolleman
me@jerven.eu

Received on Monday, 16 June 2014 16:11:25 UTC