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Re: How to query for Country Specific Data

From: Kingsley Idehen <kidehen@openlinksw.com>
Date: Sun, 24 May 2009 19:32:51 -0400
Message-ID: <4A19D923.2010707@openlinksw.com>
To: Hugh Glaser <hg@ecs.soton.ac.uk>
CC: "richard.hancock@3kbo.com" <richard.hancock@3kbo.com>, "public-lod@w3.org" <public-lod@w3.org>
Hugh Glaser wrote:
> An interesting question - should be a classic for Linked Data.
> As I understand it, your primary problem for New Zealand is that there is no reliable information about the administrative geography.
> It doesn't help for New Zealand (!), but for the UK you could use the Ordnance Survey's, which can be found in RDF via
> http://osdir.com/ml/web.semantic.linking-open-data/2008-05/msg00011.html
> We have made it linked data at os.rkbexplorer.com, with a SPARQL endpoint if you want it.
> (If people are doing this sort of thing (if you thought of doing some of it yourself), then reusing the OS ontology might be a good idea.)
>
> For the UK, it would be a case of jumping (follow-your-nose) backwards and forwards between the os and dbpedia, I suggest, using the os to find the inclusion and dbpedia to find the knowledge.
> This afternoon I did a bunch of links between them (the bigger areas and towns), to let you have a go if you like, and these can be found at our os coreference service (crs) at
> http://os.rkbexplorer.com/crs/
>
> By the way, if you want an easy way of finding out what URIs might tell you what is known about a particular place (or anything), you could try our sameAs service at
> http://www.rkbexplorer.com/sameAs/?uri=
> So New Zealand would be
> http://www.rkbexplorer.com/sameAs/?uri=http://dbpedia.org/resource/New_Zealand
> And Wellington http://www.rkbexplorer.com/sameAs/?uri=http://dbpedia.org/resource/Wellington
> and you can follow-your-nose from there.
>   
Hugh,

Assuming you sent this response before mine re. 
http://lod.openlinksw.com . How does the following not resolve this problem:

1. Go to http://lod.openlinksw.com
2. Enter pattern: New Zealand
3. Use "Type" and/or "Property" to  locate what you want
4. Once found, click on "statistics" link

Kingsley
> Best
> Hugh
>
> On 24/05/2009 08:19, "richard.hancock@3kbo.com" <richard.hancock@3kbo.com> wrote:
>
> Hi all,
>
> I am wondering what are the best queries to run against the various LOD
> datasets in order to get an idea of what Linked Data is currently
> available for a specific country, e.g. New Zealand.
>
> My plan was to start with Dbpedia and move out from there but so far my
> Dbpedia queries so far haven't yielded the results I was hoping for.
>
> My initial reasoning was that I could use the Dbpedia country URI ( i.e.
> <http://dbpedia.org/resource/New_Zealand> ) as the beginning point for my
> search and get a list of properties relating things to New Zealand using
>
> SELECT DISTINCT ?p
> FROM NAMED <http://dbpedia.org>
> WHERE {
> ?s ?p <http://dbpedia.org/resource/New_Zealand> .
> }
>
> and a list of New Zealand properties using
>
> SELECT DISTINCT ?p
> FROM NAMED <http://dbpedia.org>
> WHERE {
> <http://dbpedia.org/resource/New_Zealand> ?p ?o  .
> }
>
> The first thing I looked for were properties that would let me find towns
> and cities in New Zealand.
>
> When I couldn't find obvious properties relating New Zealand towns and
> cities to New Zealand I tried taking the URI of a specific city,
> Wellington to see what properties linked it to New Zealand.
>
> The query below shows that no property linked Wellington to New Zealand.
>
> SELECT *
> FROM NAMED <http://dbpedia.org>
> WHERE {
>  <http://dbpedia.org/resource/Wellington> ?p
> <http://dbpedia.org/resource/New_Zealand> .
> }
>
> gives no results.
>
> Going the other way showed that Wellington was the capital of New Zealand
> but I was also expecting to see another property indicating that
> Wellington was a city of New Zealand. I had hoped to find the second
> property so that I could use it to find all other cities and towns within
> New Zealand.
>
> SELECT *
> FROM NAMED <http://dbpedia.org>
> WHERE {
>  <http://dbpedia.org/resource/New_Zealand> ?p
> <http://dbpedia.org/resource/Wellington>.
> }
>
> indicates that New_Zealand has a capital via
> <http://dbpedia.org/property/capital> of Wellington
>
> The best indication that Wellington is located in New Zealand was found
> using the location property.
>
> SELECT *
> FROM NAMED <http://dbpedia.org>
> WHERE {
> <http://dbpedia.org/resource/Wellington>
> <http://dbpedia.org/property/location> ?o .
> }
>
> gives the literal "Wellington, New Zealand"@en.
>
> A scenario similar to the one between Wellington and New Zealand exists
> between Berlin and Germany but here the literal value of the location
> property proves less useful
>
> SELECT ?location
> FROM NAMED <http://dbpedia.org>
> WHERE {
> <http://dbpedia.org/resource/Berlin>
> <http://dbpedia.org/property/location> ?location .
> }
>
> gives the literal "Berlin"@en
>
> At this point I thought it was time to ask for help.
>
> For the current Linked Data sets what is the best approach to take when
> seeking to find what information has already been published for a specific
> country ?
>
> Depending on what you are looking for are some datasets better starting
> points than others? E.g. for finding the towns and cities is geonames
> (http://sws.geonames.org/) ,CIA Factbook or some other dataset, a better
> starting point?
>
> For Dbpedia are there plans to migrate properties like location
> <http://dbpedia.org/property/location> which currently use literals to use
> URIs instead?
>
> Cheers,
>
> Richard Hancock
>
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>   


-- 


Regards,

Kingsley Idehen	      Weblog: http://www.openlinksw.com/blog/~kidehen
President & CEO 
OpenLink Software     Web: http://www.openlinksw.com
Received on Sunday, 24 May 2009 23:33:28 UTC

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