Re: Data Quality Vocab for SDW from Antoine Isaac on 2016-04-15 (public-sdw-comments@w3.org from April 2016)

From: Antoine Isaac <aisaac@few.vu.nl>
Date: Fri, 15 Apr 2016 01:40:20 -0400
To: Andrea Perego <andrea.perego@jrc.ec.europa.eu>, Riccardo Albertoni <albertoni@ge.imati.cnr.it>
CC: "Heaven, Rachel E." <reh@bgs.ac.uk>, Phil Archer <phila@w3.org>, "Linda van den Brink" <l.vandenbrink@geonovum.nl>, "public-sdw-comments@w3.org" <public-sdw-comments@w3.org>
Message-ID: <57107EC4.5020203@few.vu.nl>

Hi Andrea,

On 12/04/16 13:42, Andrea Perego wrote:
> Dear Riccardo,
>
> Many thanks for having integrated the examples in the DQV specification!
>
> About this point:
>
>  >> 2. As Rachel said earlier in this thread [1], the new ISO 19115
>  >> supports the possibility of specifying resolution as vertical or
>  >> angular distance, and with level of detail.
>  >>
>  >> Based on the DQV example, I guess the first two should be modelled
>  >> as instances of dqv:Metric (:spatialResolutionAsVerticalDistance &
>  >> spatialResolutionAsAngularDistance), whereas the level of detail
>  >> should be specified with a dqv:QualityAnnotation (or a subclass -
>  >> :LevelOfDetail).
>  >>
>  >> Is this correct?
>  >
>  > Sorry, I am not sure to fully understand your question,  why  do you
>  > think that the level of detail should be expressed as a Annotation?
>
> My fault, sorry. I missed to explain the context.
>
> I was referring specifically to how this is done in ISO 19115-1:2014, where (as Rachel said [1]) the "level of detail" is specified by using element gco:CharacterString - which is meant to be used with free text / alphanumeric strings (including URLs), and not with numbers (as expected by dqv:value, right?).
>


OK, so something like in the following examples?

:spatialResolutionAsAngularDistance a dqv:Metric;
     skos:definition "Spatial resolution of a dataset expressed as angular distance"@en ;
     dqv:expectedDataType xsd:decimal ;
     dqv:inDimension dqv:precision
     .
     
:myDatasetPrecisionAS a dqv:QualityMeasurement ;
     dqv:isMeasurementOf :spatialResolutionAsAngularDistance ;
     dqv:value "[a fraction of degree]"^^xsd:decimal
     .


:spatialResolutionAsALevelOfDetail a dqv:Metric;
     skos:definition "Spatial resolution of a dataset expressed as level of detail"@en ;
     dqv:inDimension dqv:precision
     .
     
:myDatasetPrecisionLoD a dqv:QualityMeasurement ;
     dqv:isMeasurementOf :spatialResolutionAsALevelOfDetail ;
     dqv:value X .
     .


Note that in the last example, X could be a string as you suggest by using gco:CharacterString. It could also be an instance of skos:Concept that denotes a level of detail (and this has a prefLabel that corresponds to the string one would have expressed in the first way of tackling the requirement). In the latter case then we're in a borderline case where the value would make stronger the temptation to use QualityAnnotation, as the observation is not really a (numerical) measure, but something more conceptual (and possibly derived from a numerical observation).

Antoine

Received on Friday, 15 April 2016 05:40:53 UTC