- From: Frans Knibbe <frans.knibbe@geodan.nl>
- Date: Thu, 1 Sep 2016 12:31:08 +0200
- To: Jeremy Tandy <jeremy.tandy@gmail.com>, Payam Barnaghi <payam.barnaghi@gmail.com>, SDW WG Public List <public-sdw-wg@w3.org>, Linda van den Brink <l.vandenbrink@geonovum.nl>
- Message-ID: <CAFVDz42zc1JP_h3BgpOP1tG_F-fcyS3XdbL+=T0n9EB6tiddmw@mail.gmail.com>
I would like to get back to the business of resolving ISSUE-30 <https://www.w3.org/2015/spatial/track/issues/30>. Here is a more concrete proposal: Currently the Spatial Vagueness requirement <http://w3c.github.io/sdw/UseCases/SDWUseCasesAndRequirements.html#SpatialVagueness> reads: *It should be possible to describe locations in a vague, imprecise manner. For instance, to represent spatial descriptions from crowdsourced observations, such as "we saw a wildfire at the bottom of the hillside" or "we felt a light tremor while walking by Los Angeles downtown". Another related use case deals with spatial locations identified in historical texts, e.g. a battle occurred at the south west boundary of the Roman Empire.* We could change it to: *It should be possible for vague or informal expressions of locations or spatial relationships to be useful as spatial data.* *Examples of vague or informal expressions of locations are:* - *at the bottom of the hillside * - *downtown Los Angeles* - *London (has multiple definitions, so just the name is not precise)* - *the southwest boundary of the Roman Empire * *Examples of vague or informal expressions of **spatial relationships are:* - *near* - *across the street from* - *upstairs* - *at walking distance from* Are there objections to this change? If so, do you have a alternative? Do we feel that this adequately solves ISSUE-30? Thanks in advance, Frans On 19 August 2016 at 12:22, Frans Knibbe <frans.knibbe@geodan.nl> wrote: > On 19 August 2016 at 04:10, Rob Atkinson <rob@metalinkage.com.au> wrote: > >> >> 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 ;-) >> > > Hi Rob, > > I think that both requirements are missing because they are not in scope. > If the value of a measurement is published it makes general sense to > indicate the unit of measure. Likewise it is a common requirement to > indicate the uncertainty or precision of a measurement. That goes for all > numerical data, not only spatial or temporal data. > > In fact the requirements are out of scope for data on the web too. If > measurement data are published *anywhere* there should be means of > stating the unit of measurement and the uncertainty. This was rightly > reported to me when I commented on a missing best practise for using > significant digits in the Data on the Web Best Practises document. > > So yes, the coverage specification should allow for indication of units of > measurement and uncertainty, but the way we have been working is that we > understand those requirements to be known general requirements. We have > been trying to scope the explicit requirements to spatiotemporal data > only. > > Regards, > Frans > > >> >> 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/SDWUseCasesAndRequire >>>>>>>>>> ments.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 an electronic records management system. >>>>>>>>>>> ------------------------------ >>>>>>>>>>> >>>>>>>>>> >>>>>>>>> >>>>>>> >>>>>> >>>>>> >>>> >
Received on Thursday, 1 September 2016 10:31:48 UTC