This is a write-out of the short presentation I did give during Datasalon 6
at the BOZAR
in Brussels during which I expressed my concerns related to the Linked Data-ness of the upcoming next release of Europeana.Europeana
is a multi-lingual online collection of millions of digitized items from European museums, libraries, archives and multi-media collections.
It's first iteration was build using the ESE (Europeana Semantic Elements) data model.
It's a list of metadata elements being the lowest common denominator of the different data standards used in the cultural heritage sector formalized in an XML schema.
A content supplier was asked to convert its data according to this schema and put them on a OAI-PMH server where Europeana could harvest them.
A clean and powerful aggregation architecture.
Nothing wrong with that, except for the fact that the used data model is 'too' simple.
Now enter the Linked Data world
In a 'perfect' linked data world every museum, library, archive, cultural heritage organisation should publish its data according to the Linked Data principles
- being free to use whatever vocabularies which suit best their intended semantics and use case
- trying to link as much as possible to the datasets of its colleagues and to available authority lists such as VIAF, LCSH, ...
Everyone can crawl then the datasets of interest,
- build an ontology to enable:
- matching and merging
- infering new properties and relationships,
- and subsequently develop interesting applications.
I'm not saying this is simple and doesn't come with issues, but it offers the most open approach and possibilities for integration.
Europeana is working on a second generation positioning itself within this linked data and semantic web movement.
The XML ESE model will be replaced by a much, much richer data model EDM (Europeana Data Model) to be formalized with semantic web standards (RDFS/OWL).
But I wondered what this will mean for the content provider in practice?
Replacing ESE by EDM?
Will the content provider need to replace ESE by EDM data, maybe OAI-PMH to be replaced by another submission mechanism?
Even this will not be necessary since ESE will continue to be accepted.
EDM as the integrating ontology for data on the Linked Data Web?
Or will EDM be one of the merging, matching ontologies for all the different cultural heritage data flowers blossoming on the Linked Data Web?
I'm afraid it will be closer to the former.
I know this isn't on purpose.
According to the Europeana Data Model Primer, suppliers can use more specialized vocabularies as long as they provide the mapping to EDM.
- This approach doesn't expect the data to be available on the Linked Data Web; only to be submitted to Europeana.
- It contradicts the requests we get: give me the cheapest, easiest way to get on Europeana.
I have nothing against Europeana; it deserves all our support.
The problem I have is that it takes interest, resources and budget away from the real Linked Data Web.
What Europeana should do to promote the Linked Data Web
To embrace fully the Linked Data Web Europeana should:
- stimulate the cultural heritage organisations to publish their data in their richest form on the Linked Data web
- facilitate the linking between the datasets
- propose and develop authority lists for agents, events, places, concepts, ...
- work together with LOD2 to apply the most performing integration methodologies and technologies.
I do find it a little bit ackward that Europe is at the same time sponsoring the development of the best data integration technology for the highly decentralized web (LOD2
), and a concrete project for data integration (Europeana) which is very centralized.DISCLAIMER
: We earn of course our money by doing Linked Data implementations, but also by doing all types of data conversions and putting OAI-PMH into place. Only, the first one is much more future oriented and a lot more fun.
It was by getting so many ESE related RFP's during the last months that made me start worrying in the first place.
The full presentation: