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

Oh- forgot to say: it's on the agenda for discussion in Delft.

On Wed, 15 Mar 2017 at 17:58 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:
>
> ---
>
> My notes from the most recent discussion during London F2F are here:
>
>    - "samePlaceAs"
>    - it would be an IANA link relation identifier
>
>
>    - equivalence at a geographical level - without a formal definition of
>       that equivalence
>       - geography related
>       - don't express as a sub-property of, for example, "so:matches" [
>       <https://files.ifi.uzh.ch/ddis/iswc_archive/iswc/pps/web/iswc2010.semanticweb.org/pdf/261.pdf>
>       https://files.ifi.uzh.ch/ddis/iswc_archive/iswc/pps/web/iswc2010.semanticweb.org/pdf/261.pdf]
>       … we're only indicating that the _spatial_ properties match ... and
>       property hierarchies just get complicated to 95% of humans
>       - not a mathematical statement (like the topological relationships)
>       - avoid any "mereological" confusion [ :) ]
>       - nearby? (& other fuzzy relationships) ... same-place-as is _so_
>       common that we'll deal with it as a special case and _not_ cover these
>       other spatial relationships for now
>       - which ontology? IANA Link Relations
>
>
>    - ... not used today- so not a _best_ practice
>    - ... assert as a [recommended] approach to resolve problems we see in
>    evidence today- especially regarding incorrect use of owl:sameAs
>
> ---
>
> And back on the BP call on 9-Nov we said:
>
> *jtandy:* Another aspect to discuss is the reuse of identifiers ("to keep
> the global graph intact").
>
> ... But to be able to add additional information and make it retrievable
> it requires a new identifier with a sameAs-like link to the "known
> identifier"
>
> ... "samePlaceAs"?
>
> *eparsons:* samePlaceAs sounds restrictive
>
> *jtandy:* agrees, we want to avoid the strong nature of sameAs
>
> *ByronCinNZ:* likes the idea, very geographic statement. In which
> ontology would this reside?
>
> *ClemensPortele:* I think we said it would be an IANA link relation
> identifier
>
> *jtandy:* As it does not exist yet, we cannot claim it is a "best
> practice"
>
> *eparsons:* I think this problem will be hard to avoid, but it could be
> described as a way to address the issue
>
> *ChrisLittle:* worried about "samePlaceAs". How does it fit with the
> algebra of polygons?
>
> *jtandy:* we don't want to be too specific
>
> ... ... at TPAC we had a discussion about the well-defined topological
> relationships
>
> *eparsons:* to get something done quickly we should try to keep it simple
>
> ... ... relationships could be tackled later
>
> *jtandy:* so we agree that samePlaceAs is not intended as a mathematical
> statement
>
> <*ClausStadler_*>
> https://files.ifi.uzh.ch/ddis/iswc_archive/iswc/pps/web/iswc2010.semanticweb.org/pdf/261.pdf
>
> <*ClausStadler_*> "so:matches Two URIs refer to possibly distinct things
> that share all the prop- erties needed to substitute for each other in some
> graphs. Th is property is symmetric but not necessarily reflexive.
> so:matches is a super-property of so:identical ."
>
> *ByronCinNZ:* agrees, and this is probably the most important of the
> topological relationships
>
> *ClausStadler_:* Explains the paper and "so:matches" reference (see above)
>
> *jtandy:* yes, there is overlap. we want to focus on the spatial match.
>
> *ClausStadler_:* could be a sub-property
>
> *jtandy:* worried on nesting, maybe it makes it overcomplicated
>
> I agree with the concern
>
> <*eparsons*> +1
>
> *eparsons:* worried about complication, too
>
> <*AndreaPerego*> +1
>
> *ByronCinNZ:* should be a top-level relationship
>
>
>
>
>
> --
> Krzysztof Janowicz
>
> Geography Department, University of California, Santa Barbara
> 4830 Ellison Hall, Santa Barbara, CA 93106-4060
>
> Email: jano@geog.ucsb.edu
> Webpage: http://geog.ucsb.edu/~jano/
> Semantic Web Journal: http://www.semantic-web-journal.net
>
>
>