Semantic Web Company

Earlier this month the first ever Linked Data Camp took place in Vienna at the Quartier für Digitale Kunst. This two day event attracted about 35 people to discuss and to jointly work on novel applications for the Web of Data.

The first day started off with a keynote by Richard Cyganiak form DERI Galway’s Linked Data Research Center. He talked about the technical challenges that have to be overcome to allow for more Linked Data applications over heterogenous RDF data. These challenges revolve around discovery of and access to Linked Data, identifier and schema reconciliation, data fusion, quality assessment, aggregation, analytics and mining.
As Richard pointed out, the good news is “that linked data makes it possible that different people do the different steps, e.g., the publisher can help doing the identifier reconciliation by publishing sameAs links, and 3rd parties can help with access by providing a single SPARQL store over multiple related but independent datasets.” Check out the transcript
or slides for Richard’s talk.

After this keynote participants presented their topics of interest in Lightning Talks and working groups formed, some of their outcomes can be found online:
One group worked on the topic of “Dataset Dynamics”. As data in Linked Data sets change, clients having some dependency on data need to be notified about these changes. You can read about their proposed solutions here.
Another group had a go at “Expert search and profiling on the Semantic Web”, their discussions are summarized in this blog post.
Andreas Langegger demonstrated XLWrap, which is a versatile RDF wrapper for spreadsheets. A lot of feature request from participants came up (see here), so he and others worked on this handy application.

On day 2 Leigh Dodds from Talis talked about “Rights Statements on the Web of Data” (slides and transcript). Leigh raised awareness for the issue that the majority of LOD sources do not have licensing information associated with their data. This of course conflicts with the proposed openness of Linked “Open” Data, as it is doubtful whether these sources can be used for commercial puropses.

The organizers from the universities of Linz and Vienna, Joanneum Research, Gnowsis, DERI Galway, STI Innsbruck and the Semantic Web Company would like to thank all participants for making the camp a success! As with VoCamps anyone can organize a Linked Data Camp, so we hope for more camps in 2010!

The yearly organized Linking Open Data Triplification Challenge (as part of this year´s I-Semantics conference, 2 – 4 September 2009, Graz/Austria) awards prizes to the most promising triplifications of existing Web applications, Websites and data sets.

The challenge (Patron: Sir Tim Berners-Lee) is open to anyone interested in applying Semantic Web and Linked Data technologies. We envision submissions such as following:

• Applications of Linked Data tools and techniques such as for example Triplify, Virtuoso or D2RQ on custom Web applications and data sets exposing a large quantity and variety of content.
• Implementations of exporters and mappers from existing content repository formats (such as mbox mailing list archives, Bib Te X, XML-Schemes etc.) into RDF and Linked Data.
• Adoptions / configurations of Triplify for standard Web applications, such as for example Wikis, Weblogs, Webshops, Forums, Web-Gallery, ERP/CRM systems and Web-calendar software. You can find popular Web applications for example at Source Forge.
• Portings of the Triplify script into other Web application programming languages such as Python, Ruby, Perl, ASP. The Triplify script is very small (<300 lines of code) however, the port should be as compatible as possible with the current reference implementation but integrate well with the environment given by the programming language.
• Applications showcasing the benefits of Linked Data to end-users such as for information syndication, specialized search, browsing or augmentation of content.

Submissions should consist of a two page description in JUCS format of the application, accompanied by (a link to) the software source code and a link to an online demo. The descriptions should be submitted electronically via email to Michael Hausenblas with the subject Triplification Challenge Submission by May 30th, 2009.

The TRIPLE-I 2008 conference ended three days ago, yet there are a couple of loose ends I’d still like to tie up. First of all: Linked Data. Tom Heath was invited to give a keynote on “Humans and the Web of Data” – there are a variety of roles in which people may come across Tom and his LOD related work:

He administrates the site LinkedData.org (on behalf of the Linked Data community), he is the creator of Revyu.com (“Review anything!”), which won him the 1st prize in the Semantic Web Challenge 2007, he was a co-organizer of the Linked Data on the Web Workshop at this year’s World Wide Web conference in Beijing, and he was an interviewee in my 12 seconds definitions mission @ TRIPLE-I – see his micro definition of Linked Data in the vid below. (To learn more about Tom and the different roles he fulfils, look here).

Tom Heath explains Linked Data TRIPLE-I 2008 on 12seconds.tv

His keynote was not so much an introduction to Linked Data (I should expect that a conference like TRIPLE-I/I-Semantics would typically attract people who at least have an idea of what Linked Data is about), but rather a confirmation that the Web of Data is no longer a fiction, but a fact. One of the often cited proofs is the growth of the LOD dataset cloud over the last year, as shown in the image below (clicky for biggy, visualization created by Richard Cyganiak).

At the same time – and this was accordingly acknowledged by a later presentation given by Wolfgang Halb which had been prepared collaboratively by Tom, Wolfgang, Michael Hausenblas and Yves Raimond – it’s not just the sheer number of triples on the web that counts. Over the course of one year, the efforts of the Linked Data community (who seek to populate the web with open data, data in RDF) generated 4 billion triples – but only 3 million interlinks.

Their paper was an attempt to measure the size of the Semantic Web based on interlinks. A brief excerpt from the conclusion:

We have identified two different types of datasets, namely single- point-of-access datasets (such as DBpedia), and distributed datasets (e.g. the FOAF-o-sphere). At least for the single-point-of-access datasets it seems that automatic interlinking yields a high number of semantic links, however of rather shallow quality. Our finding was that not only the number of triples is relevant, but also how the datasets both internally and externally are interlinked. Based on this observation we will further research into other types of Semantic Web data and propose a metric for gauging it, based on the quality and quantity of the semantic links. We expect similar mechanisms (for example regarding automatic interlinking) to take place on the Semantic Web.

Another point raised by Tom in his key note was the issue of trust: According to his research, there are five parameters that have an influence on whether we trust a source or recommendation on the web or not: experience , expertise, impartiality (we don’t trust a travel agent, because we can’t help but believe that she is mainly going to recommend the offer of her ‘favourite’ clients), affinity, and track record, with experience, expertise and affinity being the most important ones. A semantic people search engine Tom presented, Hoonoh.com (currently in alpha), thus allows to weight search results according to these three criteria.

Tom’s concluding statement emphasized that Linking Data makes sense not for the sake of it, but for the sake of being at the service of humans: “A web of machine-readable data is even more interesting from a human than from a machine perspective,” for instance in search engines like Hoonoh.com