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A summary of some datasets and APIs in the field of linked data in education. Presented at Athens Green Hackathon, 14 December, Athens, Greece.
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Linked Data for Education – Datasets & APIsStefan Dietze
- Green Hackathon, 14 December, Athens, Greece -
TEL data vs Linked Open Data
Linked Data for Education
Relevant knowledge and data
Publications: ACM, PubMed, DBLP (L3S), OpenLibrary
(Cross-)domain knowledge & resources: BioPortal, historic artefacts in Europeana, Geonames, DBpedia, Freebase, …
Media resource metadata: BBC, Flickr, …
Explicit educational data
University Linked Data: eg The Open University UK, http://data.open.ac.uk, Southampton University, …
OER Linked Data: mEducator Linked ER (http://ckan.net/package/meducator), Open Learn LD
Schemas: LRMI (http://www.lrmi.net/), mEducator OER schema (http://purl.org/meducator/ns)
Linked Open Data
Vision: well connected graph of open Web data
W3C standards (RDF, SPARQL) to expose data, URIs to interlink datasets
=> vast cloud of interconnected datasets
Crossing all sorts of domains
32 billion triples (September 2011)
http://linkededucation.org; http://linkeduniversities.org
Data/services integration & retrieval/search APIs
Early work: educational service integration SmartLink: Linked Data registry of (educational) datasets / stores and their APIs
Discovery and lifting of educational data out of heterogeneous repositories
Transformation of heterogeneous data formats (XML, JSON...) and schemas (eg. IEEE LOM, Dublin Core) into RDF (pre-requisite for LOD compliancy)
http://ckan.net/package/smartlink & http://purl.org/smartlink
Stefan Dietze 3Green Hackathon 2012
Data/services integration & retrieval/search APIs
Early work: educational data integration
Linked Educational Resources
http://linkededucation.org/meducator
Stefan Dietze 4Green Hackathon 2012
Dereferencable resource URIs
Stefan Dietze 5tele-TASK Symposium 2012
http://ckan.net/package/smartlink
> 2000 triples so far
> 300 links to iServe
APIs (=> wiki) used by several applications
http://ckan.net/package/meducator
> 35000 triples so far
> 1000 links to DBpedia & Bioportal ontologies
APIs (=> see wiki) used by 4 applications
Data so far: SmartLink/mEducator in LOD cloud
Stefan Dietze 6Green Hackathon 2012
TEL data vs Linked Open DataChallenges
Still limited take-up (applications usually focused on small set of datasets)
Key issues
Scalability and robustness (distributed data access & retrieval, Big Data integration)
Data quality (heterogeneous providers, lack of trust)
Legal and licensing issues
Lack of benchmarks and evaluation
Stefan Dietze 7Green Hackathon 2012
“LinkedUp” Support Action
Linking Web Data for Education Project – Open Challenge in Web-scale Data Integration
EC Support Action, kickstarted in November 2012 => http://linkedup-project.eu
Goals
Push forward adoption of Web data/Linked Data in educational context
Drive technological advancement of Web data integration technologies
Approach
Open data competition (initial calls expected early 2013) incl. technical, legal and financial support
Open data curation !
Partners
+ network of associated institutions (eg BBC, Commonwealth of Learning, Talis UK, …)
Stefan Dietze 8Green Hackathon 2012
Educational data gathering - community-approach: Linked Education cloud “LinkedUp/Linked Education cloud” as subset of LOD cloud CKAN – “The DataHub” (ckan.net, most important data registry) for data collection
(analog to Linked Open Data approach) Dedicated group (“linked-education”) for cataloging educational datasets
Educational data integration & infrastructure: Linked Education graph Linked Education cloud => Linked Education graph & dataset Integration of (selected) datasets into coherent (RDF) dataset Infrastructure, unified (SPARQL) endpoint & APIs => http://linkededucation.org
LinkedUp data curationLinked Education Cloud & Linked Education Graph
Educational Data
Stefan Dietze 9Green Hackathon 2012
Linked Education graph & dataset(s)
Stefan Dietze 10Green Hackathon 2012
Stefan Dietze 11Green Hackathon 2012
<dc:title> <akt:has-title>?
OER
Publication
VideoLecture
LinkedUniversities educational videos
http://data.linkededucation.org/ns/linked-education.rdf
http://data.linkededucation.org/.... (details at the end)
6 million distinct (but linked) resources
97 million RDF triples
21.6 GB of data
Linked Education graph & dataset(s)
Stefan Dietze 12Green Hackathon 2012
Linked Education graph & dataset(s)
Entity enrichment => disambiguation & correlationVia DBpedia/Freebase
Stefan Dietze 13Green Hackathon 2012
<led:Resource-OpenLearn-2139393292>…<led:title>…laws of gravity…</led:title>…</led:Resource-OpenLearn-2139393292>
<led:Resource-BBC-519215>…<led:title>…gravitating…</led:title>…</led:Resource-BBC-519215>
Stefan Dietze 14Green Hackathon 2012
Linked Education graph & dataset(s)
Stefan Dietze 15Green Hackathon 2012
Example resource: => http://data.linkededucation.org/resource/led/92C8A5E7-7B4D-12A6-F4F2-76A6A8DC7C0A
Example query (schema alignment & categorisation):
SELECT ?resource ?title WHERE { ?resource led:title ?title FILTER regex(?title, "linear equations", "i")}
returns 1102 resources from different datasets: 659 DBLP items, 397 ACM publications, 10 LinkedUniversities educational videos
Example query (disambiguation & correlation):
SELECT distinct ?entity WHERE {?entity led:hasEnrichmentContext ?dbp_context. ?dbp_context rdf:type led:EnrichmentContext. ?dbp_context led:hasEnrichment <http://data.linkededucation.org/ontology/Enrichment/Gravitation>}
returns 5 resources (LinkedUniversities, mEducator, BBC) enriched with DBpedia concept Gravitation (even though their descriptions refer to "gravity" or "gravitational" or "laws of gravity").
Linked Education graph & dataset(s)Enabling cross-dataset queries
How to access the data (1/2)Registries and federated access to dataCKAN – The DataHub
THE public registry for open Web datasets (almost 5000 distinct datasets)
CKAN: http://thedatahub.org; LOD group: http://datahub.io/group/lodcloud
Linked Education dataset
Over 21 GB /6 million educationally relevant resources
SPARQL endpoint: http://data.linkededucation.org/openrdf-sesame/repositories/linked-learning[-selection]?query
Schema: http://data.linkededucation.org/ns/linked-education.rdf
Example resource: http://data.linkededucation.org/resource/led/92C8A5E7-7B4D-12A6-F4F2-76A6A8DC7C0A
SmartLink
SmartLink dataset: registry of educationally relevant APIs=> http://ckan.net/package/smartlink, http://purl.org/smartlink
SPARQL: http://smartlink.open.ac.uk/smartlink/sparql (dedicated APIs for search & retrieval available)
Stefan Dietze 16Green Hackathon 2012
ACM Learning Analytics and Knowledge (LAK) Dataset
Corpus of extracted metadata and full-text from ACM LAK conference series papers and related publications (expanding)
Dataset & schema description: http://www.solaresearch.org/resources/lak-dataset/
LAK Challenge: win fame, an iPad, cash rewards!
SPARQL endpoint: http://data.linkededucation.org/openrdf-sesame/repositories/lak-conference?query=%5BQUERY%5D
mEducator Linked Educational Resources
Over 600 OER (36.000 triples) from different providers
mEducator dataset: http://ckan.net/package/meducator
SPARQL: http://meducator.open.ac.uk/resourcesrestapi/rest/meducator/sparql
Schema: http://purl.org/meducator/ns
Dedicated search & retrieval APIs available (see http://linkededucation.org/meducator/)
How to access the data (2/2)Some individual datasets
Stefan Dietze 17Green Hackathon 2012
Conclusions and Outlook
Summary, ongoing work & outlook Wide range of relevant data sources & APIs available
Early cataloging (http://linkededucation.org, http://linkeduniversities.org) and integration/federation (SmartLink, mEducator Linked Educational Resources)
LinkedUp (http://www.linkedup-project.eu): data curation, assessment and exploitation
Data cataloging: http://datahub.io/en/group/linked-education for collection of “educationally relevant” datasets, categorisation and tagging
Data integration & infrastructure: unified endpoints and APIs at http://data.linkededucation.org
Getting involved Submit your own data or tools: LinkedUp Challenge, LAK Challenge, LinkedUp Call for Data
Participate as LinkedUp evaluation panelist, use case or data contributor & benefit from access to large network of organisations in Linked Data and TEL
Stefan Dietze 18Green Hackathon 2012
Contact & links
http://purl.org/dietze / [email protected]
http://linkededucation.org
http://linkedup-project.eu
Thank you!
Stefan Dietze 19Green Hackathon 2012
Credits
Davide Taibi (CNR ITD, Italy)
Harry Yu & Dong Liu (The Open University, UK)
Besnik Fetahu (L3S, Germany)
mEducator and LinkedUp teams