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Re: UCR issue 30: missing requirement

From: Rob Atkinson <rob@metalinkage.com.au>
Date: Fri, 19 Aug 2016 02:10:00 +0000
Message-ID: <CACfF9Ly1zWL_xjNm9Aj=VBD2_Kxk8pD2j2QX4DmLZ30vn3TxOQ@mail.gmail.com>
To: Rob Atkinson <rob@metalinkage.com.au>, Frans Knibbe <frans.knibbe@geodan.nl>
Cc: Joshua Lieberman <jlieberman@tumblingwalls.com>, Jeremy Tandy <jeremy.tandy@gmail.com>, Linda van den Brink <l.vandenbrink@geonovum.nl>, SDW WG Public List <public-sdw-wg@w3.org>, Payam Barnaghi <payam.barnaghi@gmail.com>
while I'm looking over the requirements document, I notice that there are
quite a lot of requirements about observations and coverages, such as
 "5.30 Observed property in coverage"  but no explicit mention of a
requirement to state the units of measure.  Perhaps simply update 5.30 to
include this?

Likewise, the only mention of precision is in the cultural heritage use
case - i would have thought there was a requirement to be able to state the
spatial and temporal precision of values. In many ways this one of the
defining requirement for making spatial "special" in terms of a BP ;-)

Cheers
Rob

On Fri, 19 Aug 2016 at 11:58 Rob Atkinson <rob@metalinkage.com.au> wrote:

> Mainly it was looking ahead :-)  But IMHO it is important to get the
> intent, then wording, of such requirements right - is it for there to be
> guidance for how a community might solve such a problem, or is it for
> interoperability in the broader ecosystem of tools - i.e. the community is
> the virtual community of  W3C or OGC standards implementers.
>
> GeoSPARQL is the latter case,
> CRS definitions is the former - but one where the OGC makes
> recommendations and uses specific CRS definitions as defaults in some
> specifications.
>
> The key thing for this requirement is whether vague descriptions are
> a) purely textual annotations (in which case we probably dont need to say
> anything about them at all in the BP)
> b) qualifications for a geometry property (in which case we probably want
> to define a vocabulary to identify such properties, and how to bind these
> to multiple geometries in a single feature - perhaps annotations need to
> apply to all provided geometries)
> c) machine-readable constructs (possibly with qualifications) - i.e. the
> ability to say A isNear B
>
> I would suggest its necessary for a BP to handle machine readable location
> descriptions with human readable annotations, i.e. cases b,c where A
> relatedTo B  and either A or B is a spatialThing. Note this covers
> providing a note about geometry per feature.
>
> Thus, I'd be tempted to say - in the BP - if the relationship can be
> expressed using the GeoSPARQL specification, then this should be used,
> either directly or by specialisation to introduce domain specific semantics
>  domain-independent spatial operation. Otherwise follow the general BP
> regarding vocabulary re-use.
>
> In, for example hydrology, a description of where a stream gauge is
> located relative to a stream confluence is actually far more precise than a
> coordinate somewhere near the confluence - which may be upstream,
> downstream or at the actual confluence in fact.
>
> In the Requirements, therefore, I'd be tempted to rephrase
> "vague,imprecise"  to "non-coordinate based" - and then identify the above
> cases and state which is in scope.
>
>
> Rob
>
>
> On Thu, 18 Aug 2016 at 20:37 Frans Knibbe <frans.knibbe@geodan.nl> wrote:
>
>> Hello Rob,
>>
>> Was your comment intended as criticism of the proposed rephrasing of the
>> spatial vagueness requirement? Or is it only looking ahead to possibilities
>> of meeting such a requirement?
>>
>> Although the primary concern of this thread is to formulate the right
>> requirement(s), I must admit in this particular case it is interesting to
>> think of possible ways of making it possible.
>>
>> Again I think a spatial ontology could be really helpful. Let's take some
>> examples of text that might be turned into spatial data:
>>
>>    1. The Carthaginian army was defeated near the southwest border of
>>    the Roman empire.
>>    2. The suspect moved from the entrance of the bank to a red car that
>>    was parked near the post box.
>>
>> The first example might come from a historical source and the second
>> could be an example of crowd sourced data, two use cases in which vague
>> spatial data are typically encountered.
>>
>> A hypothetical spatial ontology will have definitions of the concepts of
>> 'spatial thing' and 'spatial relationship'. So at least we could flag the
>> locations and the spatial relationships in these statements as such. That
>> could already be helpful.
>>
>> Now in the first example it is imaginable that a resource exists that
>> defines the terms used in a domain context. Historians studying the Roman
>> empire could make a vocabulary in which the general classes for location
>> and spatial relationships are specialised. It could have a collection of
>> linestrings marking the borders of the empire through time, and it could
>> have a definition of the spatial relationship 'near', which in historical
>> Roman texts could always mean 'a distance of at most one day's marching'.
>> Furthermore, the spot where the battle took place could be represented
>> as a 2D point geometry with unknown coordinates (by the way, a possible
>> example of why the coordinates should not be a mandatory part of a
>> geometry).
>>
>> For crowd sourced information, definitions of vague terms that are used
>> will probably be more difficult to outsource to domain vocabularies.
>> Definitions of terms can be as diverse as the crowds using the terms. But
>> at least flagging the locations and spatial relationships using the general
>> spatial ontology could be useful.
>>
>> Regards,
>> Frans
>>
>> On 18 August 2016 at 01:10, Rob Atkinson <rob@metalinkage.com.au> wrote:
>>
>>> IMHO this is covered by the general vocabulary re-use clause - such
>>> vague terms are domain specific semantics - therefore in general you should
>>> look to re-use a set of relationship properties, as defined in an ontology,
>>> published by the community of practice you intend your data to be
>>> understood by/interoperable with.
>>>
>>> In general, one should look first  to the OGC for spatial concerns, to
>>> see if such a community has either published what you need, or has a
>>> governance structure in place (a Domain Working Group) where such a
>>> vocabulary can be shared. (note that OGC will reference relevant
>>> vocabularies published by other SDOs.... so its a sensible starting point
>>> IMHO)
>>>
>>> Rob
>>>
>>> On Wed, 17 Aug 2016 at 23:10 Joshua Lieberman <
>>> jlieberman@tumblingwalls.com> wrote:
>>>
>>>> Can we distinguish between qualitative relationships such "bottom of
>>>> the hillside” which are as precise as the features being referenced,  and
>>>> fuzzy ones such as “near the hillside” that explicitly use imprecise
>>>> relationships?
>>>>
>>>> Josh
>>>>
>>>> On Aug 17, 2016, at 9:00 AM, Frans Knibbe <frans.knibbe@geodan.nl>
>>>> wrote:
>>>>
>>>> Dear group members, especially the BP editors,
>>>>
>>>> It would be great if we can resolve this sleeping issue
>>>> <https://www.w3.org/2015/spatial/track/issues/30> before the next PWD
>>>> of the UC&R document. To summarise the issue, it seems clear what the
>>>> requirement is: there is a need to be able to use vague/informal/colloquial
>>>> expressions to refer to either spatial things or spatial relationships.
>>>>
>>>> I still think the easiest solution is to change the existing Spatial
>>>> vagueness
>>>> <http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#SpatialVagueness>
>>>> requirement a bit. The core requirement would then be something like "It
>>>> should be possible to use vague or informal expressions to indicate
>>>> locations or spatial relationships". That requirement could be followed by
>>>> some examples:
>>>>
>>>> for locations:
>>>>
>>>>    - at the bottom of the hillside
>>>>    - downtown Los Angeles
>>>>    - London (has multiple definitions, so just the name is not precise)
>>>>    - the south west boundary of the Roman Empire
>>>>
>>>> for spatial relationships:
>>>>
>>>>    - near
>>>>    - across the street from
>>>>    - upstairs
>>>>    - at walking distance from
>>>>
>>>> What do you think?
>>>>
>>>> Regards,
>>>> Frans
>>>>
>>>> On 20 October 2015 at 14:04, Frans Knibbe <frans.knibbe@geodan.nl>
>>>> wrote:
>>>>
>>>>>
>>>>>
>>>>> 2015-10-16 11:15 GMT+02:00 Jeremy Tandy <jeremy.tandy@gmail.com>:
>>>>>
>>>>>> Hi Frans-
>>>>>>
>>>>>> I'm not sure that your option (1) covers the terms used for 'vague'
>>>>>> (or, more accurately, _relative_) spatial relationships. I think that we
>>>>>> might want to refer to the location of a post box unambiguously, based on
>>>>>> it's position within a topological (road) network; e.g. 150 from the
>>>>>> junction of roads A and B in the direction of [etc.] ... the junction (a
>>>>>> node in the network) might have a geometric position (e.g. collected by a
>>>>>> surveyor with GPS), but the position of street furniture may be recorded
>>>>>> using relative positions.
>>>>>>
>>>>>
>>>>> We already have a requirement for being able to use spatial
>>>>> relationships, see the Spatial relationships requirement
>>>>> <http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#SpatialRelationships>.
>>>>> If that requirement is met, it should be possible to express the location
>>>>> of a post box relative to some topographic or topological point, wouldn't
>>>>> you say?
>>>>>
>>>>> However, the ability to be vague about relative positioning does not
>>>>> seem to have been addressed yet. One might want to say that a post box is
>>>>> close to the butcher shop, or over the road from the bakery.
>>>>>
>>>>> Regards,
>>>>> Frans
>>>>>
>>>>>
>>>>>>
>>>>>> Does that help?
>>>>>>
>>>>>> Jeremy
>>>>>>
>>>>>> On Wed, 14 Oct 2015 at 13:17 Frans Knibbe <frans.knibbe@geodan.nl>
>>>>>> wrote:
>>>>>>
>>>>>>> Rachel and Jeremy, thank you for helping us solve this case.
>>>>>>>
>>>>>>> So this is about being able to use colloquial terms for both
>>>>>>> location and spatial relationships. It seems to me that the first
>>>>>>> part, colloquial terms for location is basically covered by the Spatial
>>>>>>> vagueness requirement
>>>>>>> <http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#SpatialVagueness>.
>>>>>>> Interestingly enough, this requirement has not been related to the Best
>>>>>>> Practices requirement.
>>>>>>>
>>>>>>> What we could do is:
>>>>>>>
>>>>>>>    1. Rephrase the spatial vagueness requirement a bit to make it
>>>>>>>    clearly cover examples like “the midlands”, “town centre”, how different
>>>>>>>    people define “London”.
>>>>>>>    2. Relate the spatial vagueness requirement to the Locating a
>>>>>>>    Thing use case
>>>>>>>    <http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#LocatingAThing>
>>>>>>>    and the Best Practices deliverable
>>>>>>>
>>>>>>> For the requirement to be able to use colloquial terms for spatial
>>>>>>> relationships we could either expand the definition of the Spatial
>>>>>>> vagueness requirement, or add a new requirement, so that we end up with
>>>>>>> separate requirements for spatial vagueness for locations and spatial
>>>>>>> vagueness for relationships. I would favour the first option, to keep
>>>>>>> things simple, and because there is of plenty of overlap between the
>>>>>>> requirements.
>>>>>>>
>>>>>>> Regards,
>>>>>>> Frans
>>>>>>>
>>>>>>>
>>>>>>> 2015-10-13 18:03 GMT+02:00 Jeremy Tandy <jeremy.tandy@gmail.com>:
>>>>>>>
>>>>>>>> Hi-
>>>>>>>>
>>>>>>>> Rachel is correct; 'Locating a thing' [1] (provided by @eparsons)
>>>>>>>> is the source of this requirement. The description provided in her message
>>>>>>>> is accurate. Ed also uses phrases like "upstairs", "where I left it" etc.
>>>>>>>>
>>>>>>>> It's not about geocoding; it's about relating position in human
>>>>>>>> terms ... all about context.
>>>>>>>>
>>>>>>>> FWIW, there are already some reasonable models from OGC about
>>>>>>>> describing relative positioning - usually related to position within a
>>>>>>>> topological network offset from a node in that network (e.g. position of
>>>>>>>> signage on a railway, position of a lamp post on a street etc.)
>>>>>>>>
>>>>>>>> Jeremy
>>>>>>>>
>>>>>>>> [1]:
>>>>>>>> http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#LocatingAThing
>>>>>>>>
>>>>>>>>
>>>>>>>> On Fri, 9 Oct 2015 at 17:37 Heaven, Rachel E. <reh@bgs.ac.uk>
>>>>>>>> wrote:
>>>>>>>>
>>>>>>>>> Hi Frans
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Looks like this is from the “Locating a thing” use case,
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> https://www.w3.org/2015/spatial/wiki/Working_Use_Cases#Locating_a_thing
>>>>>>>>> ...
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> It’s about vernacular geography :  human terms for relative
>>>>>>>>> spatial positioning (“upstairs”, “over the road from”) and human concepts
>>>>>>>>> of places (“the midlands”, “town centre”, how different people define
>>>>>>>>> “London”). These extents are usually vague and do not match official
>>>>>>>>> authoritative boundaries, so you can’t geocode them accurately, if at all.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> It will also be very relevant to harvesting crowd sourced data
>>>>>>>>> https://www.w3.org/2015/spatial/wiki/Working_Use_Cases#Crowd_sourced_earthquake_observation_information_.28Best_Practice.2CSSN.29
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Cheers,
>>>>>>>>>
>>>>>>>>> Rachel
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> *From:* Frans Knibbe [mailto:frans.knibbe@geodan.nl]
>>>>>>>>> *Sent:* 09 October 2015 14:11
>>>>>>>>> *To:* SDW WG Public List; Kerry Taylor; Jeremy Tandy
>>>>>>>>> *Subject:* UCR issue 30: missing requirement
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Hello.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> This is the thread for discussion of UCR issue 30
>>>>>>>>> <http://www.w3.org/2015/spatial/track/issues/30>, the Case of the
>>>>>>>>> Mysterious Missing Requirement.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> The current description reads: '*see " relative (spatial)
>>>>>>>>> relationships based on context e.g. my location [expressing location and
>>>>>>>>> places in human terms] " from *
>>>>>>>>>
>>>>>>>>> *https://www.w3.org/2015/spatial/wiki/BP_Consolidated_Narratives#linking_data
>>>>>>>>> <https://www.w3.org/2015/spatial/wiki/BP_Consolidated_Narratives#linking_data>'. Jeremy
>>>>>>>>> might know what use case it came from.'*
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> To me is not exactly clear yet what the requirement could be.
>>>>>>>>> Resolving location names in human terms to geometry is called geocoding and
>>>>>>>>> is a well established practice. Could this be about the need for having
>>>>>>>>> human language equivalents for spatial relations? I can see that would be a
>>>>>>>>> benefit for finding spatial data using a search engine.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> If we find the related use case(s) we will probably get a better
>>>>>>>>> idea of what the missing requirement could look like,
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> Regards,
>>>>>>>>>
>>>>>>>>> Frans
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>> ------------------------------
>>>>>>>>> This message (and any attachments) is for the recipient only. NERC
>>>>>>>>> is subject to the Freedom of Information Act 2000 and the contents of this
>>>>>>>>> email and any reply you make may be disclosed by NERC unless it is exempt
>>>>>>>>> from release under the Act. Any material supplied to NERC may be stored in
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>>>>>>>>> ------------------------------
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>
>>>>
>>>>
>>
Received on Friday, 19 August 2016 02:10:56 UTC

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