The document discusses the challenges and achievements of linked data and the semantic web, emphasizing the importance of standardized data sharing for knowledge integration. Key challenges identified include data quality, usability, and linking inefficiencies, while the document highlights ongoing efforts, such as the development of the LOD2 stack for managing and enriching RDF data. It showcases various use cases and the involvement of multiple organizations in advancing linked data technologies.

1. Linked Data Challenges & LOD2
Sören Auer
Universität Leipzig & OKFN Germany

2. The best way to get value from data is to give it away
in standardized formats.

3. Linked Data example
Sören Auer The Semantic Data Web 3
23.8.2011 Page 3 http://lod2.eu

4. The emerging Web of Data
achievements and challenges
• Web - a global, distributed platform for data, information and knowledge integration
• exposing, sharing, and connecting pieces of data, information, and knowledge on the Semantic Web
using URIs and RDF
Achievements Challenges
1. Coherence: Relatively few,
1. Extension of the Web with
expensively maintained links
a data commons (currently
2. Quality: partly low quality data
amounting 35 Billion facts)
July 2007 April 2008 September 2008 and inconsistencies
2. vibrant, global RTD 3. Performance: Still substantial
community penalties compared to relational
3. Industrial uptake begins 4. Data consumption: large-scale
(e.g. BBC, Thomson processing, schema mapping
Reuters, Eli Lilly) and data fusion still in its infancy
4. Emerging governmental 5. Usability: Missing direct end-
adoption in sight user tools and network effect
5. Establishing Linked Data as
a deployment path for the These issues are closely related
Semantic Web. and should ultimately lead to an
ecosystem of interlinked
July 2009 knowledge!

5. The Linked Data Lifecycle Inter-
linking/
Fusing
Manual Classifi-
revision/ cation/
authoring Enrichment
Storage/
Linked Data Quality
Querying
Lifecycle Analysis
Challenges
Evolution /
Extraction Repair
Search/
Browsing/
Exploration

6. LOD2 in a Nutshell
Creating Know le dge
out of Interlinked Data
Research focus
• Very large RDF data
management
• Enrichment &
Interlinking
• Fusion & Information
Quality
• Adaptive UI interfaces
Use Cases
• Media & Publishing
• Enterprise Data Webs
• Open Gov Data
Partners
Uni Leipzig, DERI Galway,
FU Berlin, Semantic
Web Company,
OpenLink, Tenforce,
Exalead, Wolters
Kluwer, OKFN, IMP,
Zemanta, I2G, UEP
Sören Auer – The Semantic Data Web 14.7.2011 Page 6 http://lod2.eu

7. Creating Knowledge out of Interlinked Data
LOD2 Stack
Inter-linking/
Fusing
Manual
revision/ SILK Classifi-cation/
Enrichment
authoring
OntoWiki
Storage/ Quality
Querying Virtuoso Analysis
DLlearne
D2R r
Evolution /
Extraction sindice Repair
Search/
Browsing/
Exploration
Das Web der Daten für Unternehmen . 07.04.2011 . Page 7 http://lod2.eu

8. Creating Knowledge out of Interlinked Data
LOD2 stack repository: http://stack.lod2.eu
• The LOD2 stack repository
• HOWTO start
• HOWTO contribute
• From scratch (most system knowledge required)
• From downloadable Virtual machines
• Online: http://demo.lod2.eu/lod2demo
Das Web der Daten für Unternehmen . 07.04.2011 . Page 8 http://lod2.eu

9. Creating Knowledge out of Interlinked Data
WP1: Task 1.1 Common requirements analysis and specification
Task 1.3 Early Stack Prototype (M6 12)
http://demo.lod2.eu/lod2demo
Das Web der Daten für Unternehmen . 07.04.2011 . Page 9 http://lod2.eu

10. OKFN.de
• OffeneDaten.de
• München Open
Government Day
• Offener Haushalt
• Frankfurt gestalten
• Frag den Staat
• Apps für Deutschland
• Berlin Open Data Day
• Open Aid Data
• Open Data Hackdays

11. Thanks!
• Sören Auer
• Research Group AKSW/Uni Leipzig,
http://aksw.org
• auer@uni-leipzig.de
• Open Knowledge Foundation Deutschland,
http://okfn.de