Linked Data
BCS Lunchtime Seminar
10 July 2012
Linked Data
- What is it?
- What is it for?
- What can I do with it?
Linked Data Basics
Here is a picture.
Linked Data Basics
Here is a picture.
Of Albert Einstein
Linked Data Basics
Here is a picture
Of Albert Einstein
And his famous equation: e=mc2
Linked Data Basics
Here is a picture
Of Albert Einstein
And his famous equation: e=mc2
Actually, it's a picture of a sculpture of Albert Einstein
Linked Data Basics
Here is a picture
Of Albert Einstein
And his famous equation: e=mc2
Actually, it's a picture of a sculpture of Albert Einstein
Find out more...
Linked Data Basics
Wouldn't it be great if your computer could do all that looking up for you?
Things and Documents About Them
Previous data model is an over-simplification.
HTTP GET on http://en.wikipedia.org/wiki/Albert_Einstein returns:
200 OK
Cache-Control: private, s-maxage=0, max-age=0, must-revalidate
Connection: close
Date: Sat, 07 Jul 2012 09:10:07 GMT
Server: Apache
Vary: Accept-Encoding,Cookie
Content-Language: en
Content-Length: 351336
Content-Type: text/html; charset=UTF-8
Expires: Thu, 01 Jan 1970 00:00:00 GMT
Last-Modified: Fri, 06 Jul 2012 15:21:23 GMT
Things and Documents About Them
Hence DBpedia
For each Wikipedia entry, creates two URIs:
- the resource itself (e.g. http://dbpedia.org/resource/Albert_Einstein)
- a page describing the resource (e.g. http://dbpedia.org/page/Albert_Einstein)
URIs resolved through HTTP content negotiation and 303 redirection.
Source of long-running debate, known as httpRange-14, that we will NOT get into today. See Jeni Tennison's latest blog post on the matter.
http://dbpedia.org/resource/Albert_Einstein (RDF/XML)
<rdf:Description rdf:about="http://dbpedia.org/resource/Le%C3%B3_Szil%C3%A1rd">
<dbpedia-owl:academicAdvisor rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
<dbpprop:academicAdvisors rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
</rdf:Description>
<rdf:Description rdf:about="http://dbpedia.org/resource/Stephen_Hawking">
<dbpedia-owl:influencedBy rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
<dbpprop:influences rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
</rdf:Description>
<rdf:Description rdf:about="http://dbpedia.org/resource/Nathan_Rosen">
<dbpedia-owl:academicAdvisor rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
<dbpprop:academicAdvisors rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
</rdf:Description>
<rdf:Description rdf:about="http://dbpedia.org/resource/Einstein_%28disambiguation%29">
<dbpedia-owl:wikiPageDisambiguates rdf:resource="http://dbpedia.org/resource/Albert_Einstein" />
</rdf:Description>
http://dbpedia.org/resource/Albert_Einstein (Turtle)
dbpedia:Albert_Einstein rdfs:comment "Albert Einstein was a German-born theoretical
physicist who developed the theory of general relativity, effecting a revolution
in physics. For this achievement, Einstein is often regarded as the father of
modern physics and one of the most prolific intellects in human history. He received
the 1921 Nobel Prize in Physics \"for his services to theoretical physics,
and especially for his discovery of the law of the photoelectric effect\"."@en ,
"Albert Einstein est un physicien th\u00E9oricien d'origine juive qui fut
successivement allemand, puis apatride (1896), suisse (1901), et enfin helv\u00E9tico-am\u00E9ricain
(1940). Il publie sa th\u00E9orie de la relativit\u00E9 restreinte en 1905, et
une th\u00E9orie de la gravitation dite relativit\u00E9 g\u00E9n\u00E9rale en 1915. Il
contribue largement au d\u00E9veloppement de la m\u00E9canique quantique et de la
cosmologie, et re\u00E7oit le prix Nobel de physique de 1921 pour son explication
de l\u2019effet photo\u00E9lectrique."@fr .
http://dbpedia.org/resource/Albert_Einstein (HTML)
303 See Other
Connection: close
Date: Sat, 07 Jul 2012 10:03:27 GMT
Accept-Ranges: bytes
Location: http://dbpedia.org/page/Albert_Einstein
Server: Virtuoso/06.04.3132 (Linux) x86_64-generic-linux-glibc25-64 VDB
Content-Length: 0
…
Open Government Data
Public sector holds a lot of data:
- schools & hospitals;
- elected representatives, constituencies etc.
- spending data;
- company registration data;
- statsitics
- …
Open Government Data
Most Open Government Data released as CSV (source)
Most apps are Web based and visualise a single static dataset.
Approximately 90% of the apps surveyed combine OGD with maps, mainly Google Maps and Open Street Map.
Lots of challenges remain (write up):
- Interoperability & multilingualism
- Fear
- Understanding & Empowerment
- Context & responsibility
- Show me the money
Lichfield My Area
Lichfield My Area
Bathing Water Data Explorer
Bathing Water Data Explorer
Open Government Data Around the World
Open Government Data Around the World
The 5 Starts of Linked Open Data
| ★ | Available on the web (whatever format) but with an open licence, to be Open Data |
| ★★ | Available as machine-readable structured data (e.g. excel instead of image scan of a table) |
| ★★★ | as (2) plus non-proprietary format (e.g. CSV instead of excel) |
| ★★★★ | All the above plus, Use open standards from W3C (RDF and SPARQL) to identify things, so that people can point at your stuff |
| ★★★★★ | All the above, plus: Link your data to other people’s data to provide context |
Originally developed by Tim Berners-Lee
Linked Data
BCS Lunchtime Seminar
10 July 2012
