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Re: WG discussion: shall we recommend a "samePlaceAs" property?

From: Jeremy Tandy <jeremy.tandy@gmail.com>
Date: Sun, 07 May 2017 07:51:22 +0000
Message-ID: <CADtUq_2QTjDJgwoWcNNmO=M77Wq=Rh8ew=LQ3muBc-uJeUgm-A@mail.gmail.com>
To: Linda van den Brink <l.vandenbrink@geonovum.nl>
Cc: Joshua Lieberman <jlieberman@tumblingwalls.com>, Frans Knibbe <frans.knibbe@geodan.nl>, SDW WG Public List <public-sdw-wg@w3.org>
1/ Thank you!
2/ Strange ... I've added a new section in the conclusions [1] ...
§14.5 Defining
that two places are the same

Hopefully you can confirm that you see this too now.

Cheers, Jeremy

[1]: http://w3c.github.io/sdw/bp/#c-sameplaceas

On Sat, 6 May 2017 at 08:22 Linda van den Brink <l.vandenbrink@geonovum.nl>
wrote:

> Much improved now that it's two best practices!
>
> One thing; I still see the samePlaceAs proposal in BP10, and not in the
> conclusions/gaps section.
>
> Op 6 mei 2017 om 00:08 heeft Jeremy Tandy <jeremy.tandy@gmail.com> het
> volgende geschreven:
>
> All- just a quick advisory to say that I've updated the BP doc to reflect
> our discussions in Delft about spatial thing.
>
> BP10 [1] has had what looks like a comprehensive re-write - but mostly
> this is just moving stuff around to improve the reading flow.
>
> The proposal about "samePlaceAs" has been moved to the conclusions [2] as
> it is clearly _not_ a best practice; but responds to a gap in practice. I
> also refer to the rather too general definition of schema.org/Place ...
>
> Come the finish, I didn't add a property like "colocatedAt" because I felt
> that these semantics were reasonably well covered by things like
> geonames:nearby. ... not perfect, but close.
>
> I think I have represented the difference between location and place.
>
> FWIW, the Pull Request is #811 [3] - but you might struggle to see all the
> material changes as I've moved stuff around.
>
> [1]: http://w3c.github.io/sdw/bp/#entity-level-links
> [2]: http://w3c.github.io/sdw/bp/#c-sameplaceas
> [3]: https://github.com/w3c/sdw/pull/811
>
> On Sun, 19 Mar 2017 at 16:24 Joshua Lieberman <
> jlieberman@tumblingwalls.com> wrote:
>
> Hi Frans,
>>
>> I agree that Place should be understood as a SpatialThing, but not all
>> SpatialThings should be Places. Whether relations between SpatialThings
>> should be named differently than those between SpatialModels such as
>> Geometries is a separate question.
>>
>> Topics for discussion!
>>
>> —Josh
>>
> On Mar 16, 2017, at 3:53 PM, Frans Knibbe <frans.knibbe@geodan.nl> wrote:
>>
>> Hi Josh,
>>
>> I thought the current proposal is to try to make a schema:samePlaceAs
>> property, with domain and range both being schema:Place. As it is all
>> taking place in schema.org, definitions are not very strict. But
>>  schema:Place could be taken to mean a spatial thing. A future spatial
>> ontology that defines SpatialThing could express some kind of equivalence
>> between space:SpatialThing and schema:Place. So possible properties of
>> SpatialThings, like topological relationships, could also be made
>> applicable to schema:Places. That would mean there is no need for something
>> like 'inSamePlaceAs'. For keys left in a place, spatial relationship
>> 'Within' could be used, for the supernova/black hole example spatial
>> relationship 'Equals' could be used. I must admit that it would be
>> stretching things to say that a bunch of keys is a place. But it is a
>> spatial thing.
>>
>> Let's suppose that the spatial ontology is finished and that it defines a
>> set of computable topological relationships for geometries and a set of
>> noncomputable (qualitative) topological relationships for spatial things.
>> In the latter set of relationships there will an 'Equals' relationship.
>> Wouldn't that be just what we are looking for? We could then say thing like:
>>
>> ns1:12345 space:sEquals ns2:London
>>
>> or
>>
>> :myKeys space:sWithin :myLeftFrontTrouserPocket
>>
>> (the prefix 's' in space:sWithin would mean the SpatialThing property is
>> meant, not the Geometry property)
>>
>>
>> Regards,
>> Frans
>>
>>
>>
>>
>>
>> On 16 March 2017 at 14:48, Joshua Lieberman <jlieberman@tumblingwalls.com
>> > wrote:
>>
>> Hi Frans,
>>>
>>> The problem with this use of “Place” is that it is not taken to be
>>> synonymous with “location” or “position”. Place is clearly used as a type
>>> of geographic feature that people put a name to -> “placename”. So the
>>> implication of “samePlaceAs" is that two entities are both places and in
>>> fact are the same place feature. It is as if you were saying that the keys
>>> are the same feature as the tabletop, which I think is not the intended
>>> consequence.
>>>
>>> The intent also does not seem to be that two entities share the same
>>> precise numerical position. The desired sense appears to be, rather, that
>>> one feature / SpatialThing has the same general location as another. I
>>> suggested before the two-way relation “collocated”, but “sameLocationAs”
>>> has the same implication.
>>>
>>> Looking more closely at your example,  I note the expression “in the
>>> same place”. So it makes some sense to have a property “inSamePlaceAs” to
>>> assert that two entities share a place, but it is still a bit odd not to
>>> identify the place being shared. So we would probably also need “inPlace”
>>> and “placeFor” for that purpose.
>>>
>>> —Josh
>>>
>> On Mar 16, 2017, at 9:03 AM, Frans Knibbe <frans.knibbe@geodan.nl> wrote:
>>>
>>> Hello,
>>>
>>> There is a established need for having something like 'samePlaceAs'. I
>>> think it is basically what the Subject equality requirement
>>> <https://www.w3.org/TR/sdw-ucr/#SubjectEquality> is about. It often
>>> happens that data about spatial things are held in different systems that
>>> use different models to describe the real world. There is a need to be able
>>> to state that different data representations are about the same spatial
>>> thing. I think the proposed schema:samePlaceAs could do a decent job at
>>> meeting the requirement.
>>>
>>> As for limiting the application of the term to geography (mentioned in
>>> the London F2F bullet points in the first message of this thread): Why not
>>> make it applicable to all things spatial? That way we can express things
>>> like 'you probably left your keys in the same place as yesterday' or 'the
>>> black hole is in the same place as the supernova that was seen by Kepler in
>>> 1604'. The definition of schema:Place seems to strongly hint at geographic
>>> places only. Can we assure that samePlaceAs cab be used as a spatial (not
>>> just geographical) property?
>>>
>>> Regards,
>>> Frans
>>>
>>> On 16 March 2017 at 07:02, Rob Atkinson <rob@metalinkage.com.au> wrote:
>>>
>>>
>>>> Just a reminder about the semantics of owl:sameAs if you're not fully
>>>> across it it - it means properties can be transitively assigned
>>>>
>>>> A sameAs B
>>>> A costs X
>>>> B isA FrogCollar
>>>>
>>>> means
>>>> A isA FrogCollar
>>>> B costs X
>>>>
>>>> if this is not _exactly_ what you intend, then dont use owl:sameAs
>>>>
>>>>
>>>>
>>>> On Thu, 16 Mar 2017 at 13:16 Krzysztof Janowicz <janowicz@ucsb.edu>
>>>> wrote:
>>>>
>>> I agree with Rob. Personally, I still do not see the need for the
>>>>> relation nor do I fully understand what it should be used for that is not
>>>>> covered otherwise; see my previous emails for details. Also, is this going
>>>>> to be an isolated samePlaceAs relation or is there a bigger
>>>>> picture/ontology here? Finally, owl:sameAs is not all that scary and
>>>>> dangerous as it is often being portrait. The problems with owl:sameAs were
>>>>> due to mistakes in its early usage of Linked Data. This was clearly
>>>>> something that had to be addressed and explained in 2010, but it is not
>>>>> that relevant anymore for 2017. OWL:sameAs is one of the most important
>>>>> properties on the Linked Data web.
>>>>>
>>>>> Cheers,
>>>>> Jano
>>>>>
>>>>>
>>>>>
>>>>> On 03/15/2017 05:29 PM, Rob Atkinson wrote:
>>>>>
>>>>
>>>>> If you are going to use terms that are not explicitly geographic, but
>>>>> relate to similarity, of matching you would be better off using
>>>>> skos:closeMatch, skos:exactMatch etc.
>>>>>
>>>>> This also allows you to use skos:broader/narrower with transitive
>>>>> versions, and doesnt preclude using a more nuanced geographical
>>>>> relationship that is a subProperty of skos relationships.
>>>>>
>>>>> This keeps it within the W3C canon, consistent with other OGC usages
>>>>> of SKOS, and is about _relationships between concepts_
>>>>>
>>>>> If on the other hand the semantics is explicitly about geographic
>>>>> relationship of related but distinct things, then i would suggest using
>>>>> GeoSPARQL or fall back to general advice about re-use of vocabularies.
>>>>>
>>>>> whatever vocab falls out as BP in the future should have a specific
>>>>> set of functions it supports - and the nuanced differences between the many
>>>>> similar terms it will require will probably only be understood in terms of
>>>>> what the results of such different functions would yield.
>>>>>
>>>>> Rob
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>> On Thu, 16 Mar 2017 at 10:31 Stephane Fellah <
>>>>> stephanef@imagemattersllc.com> wrote:
>>>>>
>>>>> Hi,
>>>>>
>>>>> During OGC Testbed 10, I raised the issue related to the misuse of
>>>>> owl:sameAs.
>>>>>
>>>>> Here the section relevant (12.3.10.1) from the Engineering Report
>>>>>  OGC-14-029
>>>>> <https://portal.opengeospatial.org/files/?artifact_id=59336>
>>>>>
>>>>> To denote that a place in a gazetteer is the ‘same’ as another one in
>>>>> another gazetteer, the intuitive way is to use the * owl:sameAs*
>>>>> relation. However owl:sameAs has been misused in many existing linked data
>>>>> due to misunderstanding of the rules of inference defined in OWL. The
>>>>> following paper discusses some of the issues with the misuse of owl:sameAs:
>>>>> http://www.w3.org/2009/12/rdf-ws/papers/ws21.A
>>>>>
>>>>> A separate property was proposed * gaz:sameLocationAs* instead. This
>>>>> property is transitive and symmetric, so it will infer the mapping on other
>>>>> instances.
>>>>>
>>>>>
>>>>> Regards
>>>>>
>>>>>
>>>>> Stephane
>>>>>
>>>>>
>>>>> On Wed, Mar 15, 2017 at 2:46 PM, Jeremy Tandy <jeremy.tandy@gmail.com>
>>>>> wrote:
>>>>>
>>>>> Yes. It's not place / location domain-specific... but the OSi example
>>>>> shows it being used in the way I was thinking for samePlaceAs.
>>>>>
>>>>> Jeremy
>>>>>
>>>>> On Wed, 15 Mar 2017 at 18:44, Clemens Portele <
>>>>> portele@interactive-instruments.de> wrote:
>>>>>
>>>>> Jeremy,
>>>>>
>>>>> doesn’t "similar to" has a different meaning than "same place/location
>>>>> as"?
>>>>>
>>>>> Clemens
>>>>>
>>>>> On 15 Mar 2017, at 18:58, Jeremy Tandy <jeremy.tandy@gmail.com> wrote:
>>>>>
>>>>> Hi. As agreed during the plenary call on 8-Mar, I have updated BP14 to
>>>>> include a proposal for "samePlaceAs".
>>>>>
>>>>> However, having just taken a look at an example from data.geohive.ie (the
>>>>> "Irish example" from [1]), I see use of an alternative to 'samePlaceAs':
>>>>>
>>>>> <http://open.vocab.org/terms/similarTo> : "Having two things that are
>>>>> not the owl:sameAs but are similar to a certain extent. It is thought of
>>>>> being used where owl:sameAs is too strong but rdfs:seeAlso is too loose.
>>>>> "
>>>>>
>>>>> In the snippet below you can see the relationship stated to a dbpedia
>>>>> resource:
>>>>>
>>>>> <http://data.geohive.ie/resource/county/2AE19629144F13A3E055000000000001>
>>>>>       rdf:type <http://ontologies.geohive.ie/osi#County> , geo:Feature ;
>>>>>       rdfs:label "DUBLIN"@en , "DUBLIN" , "Baile Átha Cliath"@ga ;
>>>>>       *ov:similarTo* <http://dbpedia.org/resource/County_Dublin> ;
>>>>>       ... ;
>>>>>       .
>>>>>
>>>>> What do you think?
>>>>>
>>>>> (side-bar discussions already give +1 votes from Linda and Andrea)
>>>>>
>>>>> Jeremy
>>>>>
>>>>> On Tue, 28 Feb 2017 at 21:58 Rob Atkinson <rob@metalinkage.com.au>
>>>>> wrote:
>>>>>
>>>>> I think we can only point to ad-hoc, and sometimes downright bad
>>>>> practices (owl;sameAs pointing to google maps interface.... )
>>>>> Need to add this to the "open issues" list IMHO
>>>>>
>>>>> Rob
>>>>>
>>>>> On Wed, 1 Mar 2017 at 06:04 Joshua Lieberman <
>>>>> jlieberman@tumblingwalls.com> wrote:
>>>>>
>>>>> Agreed. There is certainly interest in defining qualitative spatial
>>>>> relationships that can be asserted and inferred even if geometrically they
>>>>> are  imprecise or complex to calculate. However, “Place” is not just a
>>>>> position or even a geometry, but a type of feature. samePlaceAs asserts a
>>>>> much more detailed relationship than “collocated” or
>>>>> “notSpatiallyDisjoint”, which may be closer to what the proposers were
>>>>> considering.
>>>>>
>>>>> —Josh
>>>>>
>>>>> On Feb 28, 2017, at 1:53 PM, Krzysztof Janowicz <janowicz@ucsb.edu>
>>>>> wrote:
>>>>>
>>>>>
Received on Sunday, 7 May 2017 07:52:08 UTC

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