Re: Spatial context

I think that the question whether data are spatial data largely depends 
on the data publisher. The designation “Greater London” could be 
published as a text label, in which case it is not spatial data. It 
could also be published as a toponym, in which it is spatial data.

This discussion seems to point at an important requirement for our work, 
which may or may not be derived from use cases, but still is important: 
We need clear and universal semantics.

What makes a thing spatial? Does it have to have geometry? Does it have 
to have three dimensions? Does it need to be a terrestial object? Does 
it need to be non-fictional? All these things are debatable, but rather 
than debate them it would be good to have agreed upon semantics.

At the moment, there are some definitions out there on the semantic web. 
For example, the Location Core Vocabulary <http://www.w3.org/ns/locn> 
defines the concept 'location'. Unfortunately the definition is 
self-referencing: “any location, irrespective of size or other 
restriction”. In other words, it is very open to interpretation. Is 
“Paris” a location (knowing that there are multiple locations with that 
name)? Is Atlantis (fictional) a location? Is Olympus Mons (on Mars) a 
location?

GeoSPARQL <%28http://www.opengis.net/ont/geosparql> has definitions for 
the concept 'SpatialObject': “..everything that can have a spatial 
representation” (unfortunately the 'spatial representation' part is 
undefined) and 'Feature': “..equivalent to GFI_Feature defined in ISO 
19156:2011”. Unfortunately GFI_Feature as defined in ISO 19156:2011 is 
not a web resource and ISO 19156:2011 is not an open standard (because 
you have to pay for it). But it's a start...

Greetings,
Frans


On 2015-02-19 11:50, Ed Parsons wrote:
> This is a great discussion and I think it is central to the 
> potentially difficult overlap between the two community perspectives.
>
> I'm sure Josh will chip in but I do think we need to recognise that we 
> need to include spatial information for which it is not possible to 
> define a geometry or have linked to as an attribute - This I think is 
> what Josh means by context, I am writing this email from a location 
> within "Central London" although there is not a canonical geometry 
> that represents the shape of central London.
>
> This is an example of what Mike Goodchild calls a Platial Problem !
>
> This must be in scope, does the current wording around spatial 
> information accommodate it ?
>
> Ed
>
>
> On Thu Feb 19 2015 at 10:26:55 Andrea Perego 
> <andrea.perego@jrc.ec.europa.eu 
> <mailto:andrea.perego@jrc.ec.europa.eu>> wrote:
>
>     Andreas's mail gives me the opportunity to explain the objection I
>     raised during the call [1] about the proposal of adding "spatial
>     context" into scope question #1 [2].
>
>     My main concern is that the use of "spatial context" in the scoping
>     question may be confusing, and probably unnecessary.
>
>     In my understanding, spatial context is specified through spatial data
>     - i.e., it denotes one of their possible uses. So, "spatial data"
>     should be inclusive enough - it would cover spatial data as a whole,
>     irrespective of their use.
>
>     Thanks!
>
>     Andrea
>
>     ----
>     [1]http://www.w3.org/2015/02/18-sdw-minutes.html
>     [2]http://www.w3.org/2015/spatial/wiki/Scope_questions_and_Requirements
>
>     On Wed, Feb 18, 2015 at 10:10 PM, Andreas Harth <harth@kit.edu
>     <mailto:harth@kit.edu>> wrote:
>     > Hi,
>     >
>     > the issue I had with the term "spatial context" is that I did
>     not know
>     > what the "context" part was supposed to mean.
>     >
>     > If I understood Josh correctly, he mentioned that a geometry,
>     > a place description or a spatial feature should be referenceable
>     > in data.
>     >
>     > If "spatial context" does mean that, I'm fine with the phrasing of
>     > the scoping question.
>     >
>     > Cheers,
>     > Andreas.
>     >
>
>
>
>     --
>     Andrea Perego, Ph.D.
>     Scientific / Technical Project Officer
>     European Commission DG JRC
>     Institute for Environment & Sustainability
>     Unit H06 - Digital Earth & Reference Data
>     Via E. Fermi, 2749 - TP 262
>     21027 Ispra VA, Italy
>
>     https://ec.europa.eu/jrc/
>
>     ----
>     The views expressed are purely those of the writer and may
>     not in any circumstances be regarded as stating an official
>     position of the European Commission.
>



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