linked open data for inspire: from 3 to 5 star geospatial data francisco j. lopez-pellicer, aneta j....
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Linked Open Data for INSPIRE: From 3 to 5 star geospatial data
Francisco J. Lopez-Pellicer, Aneta J. Florczyk, Javier Nogueras-Iso, Pedro R. Muro-Medrano and F. Javier Zarazaga-Soria
INSPIRE Conference 2011, Edinburg, July 1, 2011
5 star Linked Data?
• Sir Tim Berners Lee (2010)• “This year, in order to encourage people - especially government data
owners - along the road to good linked data, I have developped this star rating system”
• Details @ http://www.w3.org/DesignIssues/LinkedData.html
• Purpose of this talk• Introduce this rating system in our context
• We’ve come part way !!! • Exemplified with datasets from Spain
• Present two 5 star Linked Data sites in Spain related to SDI nodes• Present a 5 star Linked Data recipe for INSPIRE data
1 Star
• Make your stuff available on the Web (whatever format) under an open license.
National Reference Geographic EquipmentPublic data, required attribution
Map of MTN50 catographic grid
Gazetteer
MTN50 catographic grid
Boundaries
2 Star
• Make it available as structured data (e.g., ESRI Shapefile instead of image portrayal of data).
Map of MTN50 catographic gridin png
3 Star
• Use non-proprietary formats (e.g., WKT instead of ESRI Shapefile, CSV instead of Access).
Gazetteer available only in Access format
Boundaries available only in
ESRI Shapefile format
MTN50 cartographic grid available in WKT
and ESRI Shapefile
4 Star
• Use URIs to identify things, so that people can point at your stuff (native use of RDF is not required)
(no way?)
GeoLinkedData.esinitiative makesavailable thisdata as RDF
MTN50 grid not published as RDF
5 Star
• Link your data to other data to provide context.
5 Star + Metadata
• For governement data, there should be metadata about the data itself (e.g. provenance, rights).
5 Star + Metadata + Data registry
• For governement data, their metadata should be available from an official registry (e.g. catalogue).
5 Star + Metadata + Data registry + Infrastructure
• For government data, the previous steps require a coordinate series of agreements on technology standards, institutional arrangements, and policies.
Summary
Level
On the Web • Datasets
★ • Open license (few or no limitations)
★★ • Structured data (easy to use)
★★★ • Non-propietary format (no additional license restrains)
★★★★ • URIs for things (work with the Web)• RDF data model (open standard that works with the Web)• Co-existence with other approaches (don’t replace)• Keep things simple (don’t overengineering RDF)
★★★★★ • RDF links (work with the Web)• Link to other approaches (don’t replace)
Metadata • Simple vocs. such as dcat (keeping thing simple)
Data registry • Official registry (transparency)• SPARQL (open standard that works with the Web)
Infrastructure • Agreements, Norms, Funds, Political support, …
5 Star Linked Data examples from Spain- http://geo.linkeddata.es/- http://datos.zaragoza.es/
Spanish NGI data @ http://geo.linkeddata.es/
Spanish NGI data @ http://geo.linkeddata.es/
Level
On the Web • Hydro topics of BCN200, BTN25, National Gazetteer
★ • Public data (Norm FOM/956/2008)
★★ • Vector and alphanumeric data
★★★ • Vary, including gesopatial proprietary formats
★★★★ • Developed and maintained by academia• Simple vocabulary
★★★★★ • Developed by academia• Do not link to SDI resources
Metadata • Provenance vocabulary
Data registry • CKAN (no official)
Infrastructure • National Geographic Instute (IGN) support
Saragossa City Council data @ http://datos.zaragoza.es/
Saragossa City Council data @ http://datos.zaragoza.es/
Level
On the Web • Assorted content, including data from local SDI node
★ • Law: Local statute & Law 37/2007• Web: ColorIURIS License
★★ • Points of interest and events
★★★ • Vary, including geospatial proprietary formats
★★★★ • Developed by industry, maintained by city council• Encoded as GeoRSS / RSS 1.0 = RDF• Clashes with existing Web admin practices (!)
★★★★★ • Developed by industry, maintained by city council• Do not link to SDI resources
Metadata • Dcat vocabulary
Data registry • Maintained by city council• SPARQL
Infrastructure • City council, normative and funding support
Conclusions- Do’s and don’ts about Linked Data- 5 star recipe for INSPIRE data
Conclusions: do’s and don’ts about Linked Data
• Do • Publish valuable data• Pick persistent URIs for naming
things• Dereference URIs to
representations’ URLs• Put metadata giving license and
provenance• Use RDF formats for data
transmission in addition • Use SPARQL for data and
metadata access• Keep simple• Integrate with existing systems
• Don’t• Publish all your data• Publish outdated data• Publish without explicit
license• Hide data behind forms or
applications• Publish data only in
propietary formats• Wait until you have a
complete ontology• Seek to replace existing
systems
Conclusion: 5 star recipe for INSPIRE data
Levels Topics
On the Web • INSPIRE datasets
★ • INSPIRE norms• Transposed to Web licenses
★★ • Vector data
★★★ • Representation in an open format [WE ARE ALREADY HERE!!!]
★★★★ • A simplified representation in RDF• Integrate with existing SDI geoportal/technologies
★★★★★ • Link to SDI resources
Metadata • Dcat vocabulary (crosswalk from existing metadata)
Data registry • Enable the use of SPARQL to query existing SDI catalogue
Infrastructure • Linked Data as one of the agreements of the SDI [PREREQUISITE]
Francisco J. Lopez-Pellicer
http://iaaa.cps.unizar.es/
IAAA is currently a partner in the EuroGeoSource project
http://www.eurogeosource.eu