Re: ACTION-96 linking to related identifiers

Bill: see http://w3c.github.io/sdw/bp/#include-search-api ... currently
just the BP label only. Jeremy

On Wed, 2 Dec 2015 at 13:37 Jeremy Tandy <jeremy.tandy@gmail.com> wrote:

> I can see that ...
>
> Under Exposing datasets through APIs
> <http://w3c.github.io/sdw/bp/#bp-exposing-via-api> we have Best Practice
> 28: Expose entity-level data through ‘convenience APIs’
> <http://w3c.github.io/sdw/bp/#convenience-apis>  which *will* say that
> the publisher needs to design APIs with the target consumer in mind;
> creating an API that does the things they need. We've not explicitly
> mentioned search/reconciliation; it's a good example.
>
> Thinking about this, if you _are_ going to provide an API it really would
> be best practice to provide a search operation. Else how do you find the
> specific resource you want???
>
> I'll add this to the BP doc (hoping that you'll help provide some content
> in due course).
>
> Jeremy
>
> On Wed, 2 Dec 2015 at 13:30 Bill Roberts <bill@swirrl.com> wrote:
>
>> Thanks Jeremy - I think you've listed the most important aspects.  One
>> potential additional best practice for consideration might be a
>> recommendation to data publishers to provide some form of
>> search/reconciliation API, particularly important with non-guessable URL
>> patterns.
>>
>> On 2 December 2015 at 13:23, Jeremy Tandy <jeremy.tandy@gmail.com> wrote:
>>
>>> Hi Bill, Jon ...
>>>
>>> Great content along with some very useful examples that we (BP editors)
>>> can incorporate.
>>>
>>> I think that the subject boils down to two best practices ...
>>>
>>> From Expressing spatial data
>>> <http://w3c.github.io/sdw/bp/#bp-expressing-spatial> we have Best
>>> Practice 13: Assert known relationships
>>> <http://w3c.github.io/sdw/bp/#semantic-rels> which *will** say
>>> something along the lines of "if you know some relationships between
>>> (spatial) Things then publish them - because it's hard to figure out
>>> relationships from scratch" as your examples illustrate.
>>>
>>> And From Linking Data <http://w3c.github.io/sdw/bp/#bp-linking> we have Best
>>> Practice 20: Provide meaningful links
>>> <http://w3c.github.io/sdw/bp/#meaningful-links> (include the right
>>> semantics), Best Practice 21: Link to spatial Things
>>> <http://w3c.github.io/sdw/bp/#link-to-spatialthings> (link up the
>>> Things rather than the information objects that describe them e.g. geometry
>>> objects) and Best Practice 22: Link to resources with well-known or
>>> authoritative identifiers
>>> <http://w3c.github.io/sdw/bp/#link-to-auth-identifiers> (reference
>>> other people's well established resources & identifiers thereof). The
>>> middle one of these needs some work methinks because it's clearly useful to
>>> link a Thing to its geometric description ... but we want to create a
>>> network of related resources using the identifiers for the Things.
>>>
>>> * "will" say ... because I've not finished writing things up yet :-)
>>>
>>> Thanks Bill. Jeremy
>>>
>>> On Sun, 29 Nov 2015 at 16:11 Jon Blower <j.d.blower@reading.ac.uk>
>>> wrote:
>>>
>>>> Hi Bill, all,
>>>>
>>>> Just wanted to say that I found this to be an extremely helpful and
>>>> informative post, thanks!
>>>>
>>>> the BP document might be able to help by categorising some of the most
>>>> common relationships and perhaps suggest examples of appropriate matching
>>>> vocabulary terms.
>>>>
>>>>
>>>> Yes, I agree. Some of these issues are very characteristic of spatial
>>>> data and bang in scope for a BP document I think. We often see abuse of
>>>> owl:sameAs when a weaker term would be more appropriate. Enumerating the
>>>> options and use cases would be very helpful.
>>>>
>>>> (This has particular local relevance to us here - the University of
>>>> Reading is actually mostly in the Wokingham district, although most people
>>>> would still refer to it as part of the Reading urban area. “Colloquial
>>>> Reading” is different from “administrative Reading”, as it is in probably
>>>> most cities.)
>>>>
>>>> Cheers,
>>>> Jon
>>>>
>>>>
>>>> On 26 Nov 2015, at 18:29, Bill Roberts <bill@swirrl.com> wrote:
>>>>
>>>> Hi BP-editors
>>>>
>>>> Here are some initial thoughts on the issues of linking from your own
>>>> Spatial Thing to other identifiers for the same thing or related things.
>>>>
>>>> This action is to expand the text in section 7.2 of the BP draft that
>>>> currently says:
>>>>
>>>> "it's useful to have hyperlinks to things like Geonames, wikipedia, OSM
>>>> etc (see list on the mailing list, keyword: stamp collecting)"
>>>>
>>>> As per http://www.w3.org/DesignIssues/LinkedData.html item 4, it's
>>>> useful for people to link their data to other related data. In this context
>>>> we're most frequently talking about either Spatial Things and/or their
>>>> geometry.
>>>>
>>>> There are many useful sets of identifiers for spatial things and which
>>>> ones are most useful will depend on context.
>>>>
>>>> I think there are two main challenges here - discovering relevant URIs
>>>> that you might want to connect to, deciding what is the nature of the
>>>> relationship between your original URI and potential link targets, and then
>>>> finding an existing vocabulary term that accurately reflects that
>>>> relationship.
>>>>
>>>> As an example, let's take Edinburgh. In some recent work with the
>>>> Scottish Government, we have an identifier for the City of Edinburgh
>>>> Council Area - i.e. the geographical area that Edinburgh City Council is
>>>> responsible for:
>>>>
>>>> http://statistics.gov.scot/id/statistical-geography/S12000036
>>>>
>>>> (note that this URI doesn't resolve yet but it will in the next couple
>>>> of months once the system goes properly live)
>>>>
>>>> Here are some identifiers for Edinburgh and/or information about it
>>>> that we might want to link to, together with notes about how I found out
>>>> about them.
>>>>
>>>> http://statistics.data.gov.uk/id/statistical-geography/S12000036
>>>>
>>>> My identifier is directly based on this one, but the Scottish
>>>> Government wanted the ability to create something dereferenceable,
>>>> potentially with additional or different info to the data.gov.uk one.
>>>> We're happy these two are owl:sameAs
>>>>
>>>> https://en.wikipedia.org/wiki/Edinburgh
>>>> Found by a google search for Edinburgh site:wikipedia.org).  This is a
>>>> page about a closely related but perhaps less specific concept of the
>>>> place. Possible document vs thing distinctions to be made here.  Possible
>>>> relationships: rdfs:seeAlso, schema:sameAs ? foaf:page?
>>>>
>>>> http://dbpedia.org/resource/Edinburgh
>>>> I know the pattern for changing a wikipedia URI into a dbpedia one, so
>>>> found it that way.  Relationship: "more or less the same as" but not sure
>>>> I'd want to go as far as the strict semantics of owl:sameAs
>>>>
>>>> http://data.ordnancesurvey.co.uk/id/50kGazetteer/81482 (Edinburgh)
>>>> Found by OS gazetteer search service for 'Edinburgh' then checking the
>>>> labels of the results that came up.  OS give it a type of 'NamedPlace' and
>>>> give it some coordinates.
>>>>
>>>> http://data.ordnancesurvey.co.uk/id/50kGazetteer/81483 (Edinburgh
>>>> airport)
>>>> Also found by the same OS gazetteer search service for 'Edinburgh'.
>>>> This is clearly not the same as my original spatial thing, but I might want
>>>> to say something like 'within' or 'hasAirport'.
>>>>
>>>> http://data.ordnancesurvey.co.uk/id/7000000000030505
>>>> Found by a search for 'Edinburgh' in the OS 'Boundary Line' service
>>>> that contains administrative and statistical geography areas in the UK.
>>>> The first results of the search were parliamentary constituencies - had to
>>>> scroll down and look for one that had a stated rdf:type that matched what I
>>>> was looking for.  It's probably safe to say my identifier is owl:sameAs
>>>> this one.
>>>>
>>>> http://sws.geonames.org/2650225/
>>>> Found with the Geonames search service:
>>>> http://api.geonames.org/search?name=Edinburgh&type=rdf&username=demo
>>>> Once you have found a place in geonames, there are other useful
>>>> services to find things that are nearby etc. Not sure exactly what this is,
>>>> though it has a RDF type of http://www.geonames.org/ontology#Feature
>>>>
>>>> http://www.openstreetmap.org/relation/1920901  (administrative
>>>> boundary)
>>>> machine readable data:
>>>> http://www.openstreetmap.org/api/0.6/relation/1920901
>>>> Found via the search box at www.openstreetmap.org.
>>>> see also
>>>> http://nominatim.openstreetmap.org/details.php?place_id=127903534
>>>> and http://www.openstreetmap.org/node/17898859 (node - somewhere
>>>> around the centre of Edinburgh)
>>>> I'm not sure of all the options with OSM - I'm sure others in the WG
>>>> know more -but it has identifiers for nodes, ways and relations, though it
>>>> seems that these identifiers tend to change quite frequently as the map is
>>>> edited.
>>>>
>>>> The outcome of this example is that it takes a bit of prior knowledge
>>>> and intelligent manual guesswork to find related URIs.  Some services, eg
>>>> OS, have useful search facilities, but the results may still need some
>>>> interpretation. Recommending some standard approach to providing a search
>>>> facility (or 'reconciliation API') for a collection of spatial data might
>>>> be a useful best practice.
>>>>
>>>> Working out how to accurately describe the relationship is hard in
>>>> general and the BP document might be able to help by categorising some of
>>>> the most common relationships and perhaps suggest examples of appropriate
>>>> matching vocabulary terms.
>>>>
>>>>
>>>>
>>>>
>>>>
>>