DATASUPPORT OPEN Metadata quality is about ... (2/3) • The conformance of your metadata to accepted standards – is the metadata conforming to a specific metadata standard or an Application Profile?
e.g. the description of a dataset conforms to the DCAT-AP.
• The consistency of your metadata – does the data not contain
contradictions?
e.g. not having multiple and contradictory license statements for the same piece of data. • The credibility and provenance of your metadata – is the metadata based on trustworthy sources?
e.g. linking to reference data published and managed by a stable organisation (e.g. the EU Publications Office).
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DATASUPPORT OPEN Metadata quality is about ... (3/3) • The processability of the metadata – is the metadata properly machine-readable?
e.g. making the metadata of a dataset available in RDF and/or XML, and
not as free text.
• The relevance of the metadata – does the metadata contain the
right amount of information for the task at hand?
e.g. limit the information to optimally serve the users’ needs.
• The timeliness of your metadata – is the metadata corresponding to
the actual (current) characteristics of the resource and is it published
soon enough?
e.g. indicating the last modification date of the resource, thus making sure the metadata is fresh so that users will see the latest information. Slide 30
DATASUPPORT OPEN Exchanging metadata of datasets Mapping your metadata to a common metadata vocabulary, such as the DCAT-AP, and exchanging the metadata across platforms.
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Homogenising metadata
When exchanged between systems, metadata should be mapped to a
common model so that the sender and the recipient share a common
understanding on the meaning of the metadata.
•
On the schema level metadata coming from different sources can be based
on different metadata schemas, e.g. DCAT, schema.org, CERIF, own
internal model...
•
On the data (value) level, the metadata properties should be assigned
values from different controlled vocabularies or syntaxes, e.g.:
Language: English can be expressed as http://publications.europa.eu/resource/authority/language/ENG or as http://id.loc.gov/vocabulary/iso639-1/en
Dates: ISO8601 (“20130101”) versus W3C DTF (“2013-01-01”) Slide 32
DATASUPPORT OPEN Example: Homogenising metadata about datasets The DCAT Application Profile for data portals in Europe The DCAT-AP can be used as the common model for exchanging metadata with open data platforms across Europe and/or with a data broker (e.g. The Open Data Interoperability Platform - ODIP). Slide 33
EXPLORE
FIND
IDENTIFY
SELECT
OBTAIN
Public admi nistrations
Busi nesses
Standar disation bodi es
Academia
Data Portal
Data Portal
Data Portal
Data Portal
Data Portal
Data Portal
Metadata
Broker
Data
Consumers
See also:
http://joinup.ec.europa.eu/asset/dcat_application_profile/home
DATASUPPORT
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Mapping example – data.gov.uk
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dct:title (Dataset)
dct:description
dct:publisher
dct:title (Distribution)
Dcat:accessURL
dct:language
dcat:keyword
dct:license
dcat:downloadURL, dct:issued,
dct:format, dct: description
dct:spatial
dct:theme
dct:issued
dct:modified
adms:contactPoint
dct:temporal
DATASUPPORT
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What can the Open Data Interoperability Platform
do?
• Harvest metadata from an Open
Data portal.
• Transform the metadata to RDF.
• Harmonise the RDF metadata
produced in the previous steps with
DCAT-AP.
• Validate the harmonised metadata
against the DCAT-AP.
• Publish the description metadata as
Linked Open Data.
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ODIPP
Pan-European
Data portal
See also:
http://www.slideshare.net/OpenDataSupport/promoting-the-re-use-
of-open-data-through-odip
DATASUPPORT
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Conclusions
• Metadata provides information on your data and resources. The
quality of the metadata directly affects the discoverability and reuse
of your the resources.
• A structured approach should be followed for metadata management.
• The metadata lifecycle extends the lifecycle of datasets (metadata
before publication and after deletion).
• Homogenised metadata enable the operation of metadata brokers,
which can in turn lower the access barriers to your resources, leading
to improved visibility and discoverability, and thus increasing their
reuse potential.
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DATASUPPORT OPEN Group exercise and questions Slide 37 In groups of two, select one dataset from your country and describe it with the DCAT Application Profile.
Does your organisation have a minimum set of metadata to be provided together with Open Data?
What would be the main barriers, according to you, for the (re)use of standard controlled vocabularies in your metadata?
Do you have any data and/or metadata governance methodology at the corporate level?
http://www.visualpharm.com http://www.visualpharm.com http://www.visualpharm.com http://www.visualpharm.com Take also the online test here!
DATASUPPORT OPEN Thank you! ...and now YOUR questions? Slide 38
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References
Slide 6, 7:
• NISO. Understanding Metadata.
http://www.niso.org/publications/press/UnderstandingMetadata.pdf
Slide 9:
• Dublin City University. Chapter 3: Introduction to XML.
http://wiki.eeng.dcu.ie/ee557/g2/326-EE.html
• W3C. RDF Primer. http://www.w3.org/TR/rdf-primer/
Slide 12:
• http://gondolin.rutgers.edu/MIC/text/how/catalog_glossary.htm
• Dublin Core. Example XML Schema.
http://dublincore.org/schemas/xmls/qdc/dc.xsd
• Dublin Core, Example RDF Schema.
http://dublincore.org/2012/06/14/dcterms.rdf
Slide 14, 33:
• The ISA Programme. DCAT Application Profile for Data Portals in Europe - Final
Draft.
https://joinup.ec.europa.eu/asset/dcat_application_profile/asset_release/dcat-
application-profile-data-portals-europe-final-draf
Slide 18:
• ListPoint. ObjectInCrimeClass.
http://www.listpoint.co.uk/CodeList/details/ObjectInCrimeClass/1.2/1
Slide 19: • Publications Office. Countries Name Authority List. http://open- data.europa.eu/en/data/dataset/2nM4aG8LdHG6RBMumfkNzQ
Slide 39 DATASUPPORT OPEN Further reading Understanding Metadata, NISO. http://www.niso.org/publications/press/UnderstandingMetadata.pdf
Ben Jareo and Malcolm Saldanha. The value proposition of a metadata driven data governance program. Best Practices Metadata. May 2012. https://community.informatica.com/mpresources/Communities/IW2 012/Docs/bos_30.pdf
John R. Friedrich, II. Metadata Management Best Practices and Lessons Learned. The 10th Annual Wilshire Meta-Data Conference and the 18th Annual DAMA International Symposium. April 2006. http://www.metaintegration.net/Publications/2006-Wilshire-DAMA- MetaIntegrationBestPractices.pdf
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Related initiatives
Metadata Management. Trainer screencasts,
http://managemetadata.com/screencasts/msa/
MIT Libraries. Data Management and Publishing. Reasons to Manage
and Publish Your Data, http://libraries.mit.edu/guides/subjects/data-
management/why.html
ISA Programme. DCAT Application Profile for European Data Portals,
https://joinup.ec.europa.eu/asset/dcat_application_profile/descripti
on
Generating ADMS-based descriptions of assets using Open Refine
RDF, https://joinup.ec.europa.eu/asset/adms/document/generate-
adms-asset-descriptions-spreadsheet-refine-rdf
The Dublin Core Medatata Initiative, http://dublincore.org/
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DATASUPPORT
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