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

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:
>
> Hi,
>
>
> Generally speaking I don't think that a predicate as samePlaceAs would be
> very useful. As far as I recall, Todd Pehle tried to introduce such
> predicate a few years ago and it was not really used.
>
> First, we would also need samePersonAs, sameEventAs, and so forth, and
> secondly, the meaning of samePlaceAs remains unclear. The issue is not only
> that owl:sameAs is more formal in a mathematical sense (which, as stated in
> this thread, is not always desired), it also related to URIs to each other
> by stating that both of them point to the same feature (e.g., the same
> place in the physical world).  What would samePlaceAs do? If it would
> relate two places (not URIs), what does it mean for two places to be the
> same or even similar?
>
> Cheers,
> Jano
>
>
>
> On 02/28/2017 02:38 AM, Kerry Taylor wrote:
>
> +1
>
> *From:* Jeremy Tandy [mailto:jeremy.tandy@gmail.com
> <jeremy.tandy@gmail.com>]
> *Sent:* Tuesday, 28 February 2017 2:11 AM
> *To:* Bill Roberts <bill@swirrl.com> <bill@swirrl.com>; SDW WG Public List
>  <public-sdw-wg@w3.org> <public-sdw-wg@w3.org>
> *Subject:* Re: WG discussion: shall we recommend a "samePlaceAs" property?
>
> Thanks Bill.
>
> > Probably a better option would be to propose it to danbri for addition
> to schema.org as a property for things of type schema:Place ?
>
> You're right that that sounds like a better home.
>
> @danbri: what do you think? (& can you remind us how we might propose this
> for schema.org's consideration)
>
> Thanks. Jeremy
>
>
> On Mon, 27 Feb 2017 at 13:43, Bill Roberts <bill@swirrl.com> wrote:
>
> I support creating a samePlaceAs relation. As well as an IANA link
> relation, can we have a URI for it to allow use in RDF?
>
> Possibly related, I see in BP10 that we refer to ongoing work to update
> GeoSPARQL - what's the status of that? Would this property/relation make
> sense as part of the new GeoSPARQL? Maybe the deliberate vagueness of
> 'samePlaceAs' might not fit well with the otherwise generally precise
> geosparql relationships.
>
> Probably a better option would be to propose it to danbri for addition to
> schema.org as a property for things of type schema:Place ?
>
>
>
> On 27 February 2017 at 11:44, Jeremy Tandy <jeremy.tandy@gmail.com> wrote:
>
> Hi - for this sprint in development of the Best Practice document, we're
> updating BPs about "linking" and "vocabularies" ...
>
> On multiple previous occasions (most recently the London F2F) we've
> mentioned that we should propose a "samePlaceAs" property. In essence, I
> think we see this as a subjective statement (that a human might make)
> rather than a mathematical / topological statement, matching on the spatial
> characteristics only.
>
> This addresses the concerns about the VERY restrictive owl:sameAs. At
> TPAC2016, @clemens said that a "relaxed relationship is better [for
> cross-referencing identifiers] (e.g. samePlaceAs) … but if you _can_ state
> owl:sameAs then you should do so … " [from my notes]
>
> We said at TPAC2015 "samePlaceAs would be a 'social relationship' - based
> on people's perception".
>
> The domain and range should both be "spatial things" (which definition of
> spatial thing do we refer to - the new one coming from @josh's work or
> w3cgeo:SpatialThing?
>
> We're looking to resolve this question BEFORE the Delft F2F.
>
> WG members: what do you think?
>
> Many thanks, Jeremy
>
> further notes below:
>
> ---
>
>
>