Reference works such as encyclopedias, glossaries, thesauries or catalogues function as guides to a scholarly domain as well as anchor points and manifestations of scholarly work. On the web of Linked Data, they can perform a key function of interlinking resources related to the described concepts. In effect, this means they can be enriched by creating new links between and within different encyclopedias. This function could revolutionize the work of digital humanists’ and become the bread and butter of their research diet.

To our almost certain knowledge JudaicaLink is the first such initiative and platform in the field of Jewish studies.

JudaicaLink: a plaform for access to Linked Data versions of encyclopedias

Like with many pioneering LOD publishing efforts, the first challenge was to persuade the publishers and maintainers of such reference works to give their permission to create a Linked Data version of their encyclopedia and publish it on JudaicaLink.org. Provided the work is already online, the minimal requirement is that the URLs of the articles in the encyclopedia remain stable.  It is also possible to publish an LOD version of a given work on the publishers own website provided they have the technical infrastructure and capacity to do so. In this case, JudaicaLink can provide information and a central search functionality.

The YIVO Encyclopedia of Jews in Eastern Europe

We have been fortunate that after some discussion the leaders of the YIVO Institute for Jewish Research in New York saw the potential of LOD for their extraordinary YIVO Encyclopedia of Jews in Eastern Europe and gave us the go ahead. From the point of view of a Linked Data enthusiast, the YIVO Encyclopedia is really a great resource. All articles are highly interlinked, often they even provide a hierarchy of sub-concepts described under a superordinate concept. Links to glossary terms provide further terminological control.

An example of topic headings from the YIVO Encyclopedia of Jews in Eastern Europe published in a LOD format

Encyclopedia of Russian Jewry

Recently, JudaicaLink announced also the first release of the Encyclopedia of Russian Jewry (Rujen), published in Moscow since 1994, as Linked Open Data. Rujen is not as interlinked as YIVO and the articles are much shorter on average, but it contains many more articles (about 20,000 compared to about 2,500 YIVO articles). The first obvious feature of Rujen for English-speaking people is the language: it’s Russian. The Cyrillic alphabet raises an important question regarding Linked Data: how to coin the URIs for the articles. We are still considering different solutions. Basically, there are three options based on the actual identifier, the Cyrillic title of the article:

1. Use a percent-encoded URI where the Cyrillic letters are represented by numbers. For example: http://data.judaicalink.org/data/rujen/%D0%93%D0%B0%D1%82%D0%BE%D0%B2_%D0%A8%D0%B0%D0%BF%D1%81%D0%B5%D0%BB%D1%8C_%D0%B3%D0%B8%D1%80%D1%88%D0%B5%D0%B2%D0%B8%D1%87. This is technically straightforward, but has several disadvantages. First of all: no one can read it, not even Russians. We tested it. Second, people could inadvertently use the decoded form, because the browser conveniently decodes the URI when entered in the address line. But this would be a different URI, actually a IRI, which brings us to the next option:
2. Use an Internationalized Resource Identifier, an IRI. For example: http://data.judaicalink.org/data/rujen/гатов_шапсель_гиршевич. This is perfectly readable (at least by Russians) and probably the option to be preferred. However, it is not clear if all applications support IRIs correctly and we would like to have the data as easily accessible as possible. Therefore, and also because we wanted to try it, we decided on the next option:
3. Use a transliterated URI. For example: http://data.judaicalink.org/data/rujen/gatov_shapselj_girshevich. Again, this is perfectly readable, and since Rujen is mostly about persons and locations, people familiar with the Latin alphabet can make sense of it. However, there are drawbacks. We did not transliterate just because of our widely shared ignorance of the Cyrillic alphabet. We adopted this option because we wanted to have valid URIs, for the sake of backwards-compatibility and technical interoperability. This means using only the 26 common Latin letters, no diacritics, no special characters. And the transliteration should be simple, based on a lookup-table that translates every Cyrillic letter consistently to one or more Latin characters. This is obviously not an ideal way to transliterate and, according to our tests with our nice colleagues from Belarus and Russia, it quite often produces somewhat strange results for native speakers. However, they assured us that it is still readable and not insulting.

Actually, there is also a fourth option that is completely different: using some kind of numbering or code scheme (for example a hash value of the title), but despite leading to shorter URIs, this again has the effect that no one can make sense of it, similar to option 1. There are people who advocate this approach precisely for this reason: a URI should not contain possibly misleading semantics. And, of course, a number does not show an arbitrary preference for a language or an alphabet.

So, we settled for transliteration as our first attempt, but we are curious about your ideas and opinion. After reading this long and hopefully interesting digression, you are probably much more interested in the question: how can I access this LOD resource?

The easiest way is the following: while browsing the YIVO Encyclopedia, you can access the data representation by simply replacing www.yivoencyclopedia.org/article.aspx/ with data.judaicalink.org/data/yivo/ in the URL field of the browser. For convenience, you can also use our bookmarklets. They are provided together with additional information for each encyclopedia here. Just drag and drop them to your bookmarks and when you click on this bookmark while on an encyclopedia article, you will be directed to the Linked Data version. For an even quicker look, you can also just start at the concept used above in option 3, or for YIVO, for example here: http://data.judaicalink.org/data/html/yivo/Abramovitsh_Sholem_Yankev.

All in all, JudaicaLink now provides access to 22,808 concepts in English (approx. 10%) and in Russian (approx. 90%), mostly locations and persons.

JudaicaLink gets links

From the beginning our vision was not only about the provision of stable URIs and data for concepts described in the encyclopedias. It was also about the generation of links between these resources and other linked data resources on the Web. In a first run, we used Silk to generate links between JudaicaLink and the following sources:

• DBpedia
• DM2E
• Freebase
• Gemeinsame Normdatei (Authority files of the German National Library)
• GeoNames
• Linked Geodata
• New York Times

All the links have been created automatically and are primarily based on the labels of the resources, so some wrong links are to be expected. Nevertheless this is an important first step. For the present, we provide the links directly together with the resource descriptions (as owl:sameAs links), but we will separate them with proper identification of the provenance as soon as we are able to use more sophisticated linking approaches. One immediate benefit from this simple linking is that we could already generate links between both encyclopedias. This works because several sources, like DBpedia, are multilingual and therefore links to both encyclopedias could be established. Whenever a single resource has two links to one resource in each encyclopedia, an additional link establishing the identity of these two resources could be inferred.

JudaicaLink arrives in the Cloud

With all these links, JudaicaLink is now also part of the famous LOD Cloud that was released recently in its latest version. You can find us at about 4 o’clock, close to the border and right beside our neighbour project DM2E.

We hope the readers of this blog will spread the word and help us to convince more publishers to work with us. And do let us know what you think of JudaicaLink and what additional ideas you have. We look forward to hearing from you!

Kai Eckert, University of Mannheim

Lena Stanley-Clamp, EAJC

Jewish Studies were one of the first academic communities to make use of digital resources with the Responsa project which began in 1967.Butis it possible that the present advances in Digital Humanities and many researchers in Jewish studies are like ships in the night that are going to pass by, and probably not meet again?

Ketubah, Herat, 5628 Ḥeshvan 16
[1867 November 14], Ket 270

The Judaica Europeana project and network of libraries, museums and archives which hold digital collections has uploaded millions of digital objects to Europeana. This process continues in the framework of the DM2E and AthenaPlus projects. Led by the European Association for Jewish Culture, the partners in the network will in the coming months integrate in Europeana some of the most valuable resources for Jewish studies: the metadata of the collections from the Center for Jewish History in New York (the YIVO and the Leo Baeck Institutes), the JDC Archives, the Jewish Theological Seminary Library, the Jewish Museum in Prague and many others. The latest Judaica Europeana newsletter presents the highlights of some of these collections.

But will anything be done to ensure that these magnificent collections – digitized at great expense with public or charitable funding ― are used to their full potential? Will the opportunities of the Linked Open Data web and the growing box of open-source tools find many takers in the Jewish Studies community? As they used to say: you can lead a horse to the water, but you can’t make it drink….

Dov Winer, Judaica Europeana’s Scientific Manager, has been arguing for some time that Digital Humanities and LOD have the potential to revolutionize Jewish Studies. The time is ripe: the DM2E project and its experts have been working on modelling the scholarly domain and developing award-winning research tools that respond to the needs of scholars. The DM2E project also provides a platform for the integration of Jewish-content metadata in Europeana.

So what’s next?

DM2E and Judaica Europeana are currently involved in converting vocabularies and encyclopaedias into formats which make them available as Linked Open Data and therefore capable of enriching the metadata of Jewish content and provide contextual meanings. This initiative, which is driven by Dov Winer of EAJC and Kay Eckert of the Research Group on Data and Web Science at Mannheim University, will soon result in the publication of The YIVO Encyclopaedia of Jews in Eastern Europe in a LOD format. The PUNDIT and ASK tools, winners of the 2013 LODLAM Challenge, are freely available with tutorials in four languages, on the DM2E website. The newsletters of Judaica Europeana, disseminated widely to the Jewish studies scholars, have been promoting the Digital Humanities agenda and these new tools to their potential constituencies and users. The work of Judaica Europeana and DM2E will be brought to the attention of participants in the forthcoming Xth Congress of the European Association for Jewish Studies in Paris: on 21 July, our partners will present captivating research in a panel entitled New perspectives on Jewish and non-Jewish relations in modern European culture based on Judaica Europeana digital collections.

Dov Winer, in his paper ‘Feeding Digital Humanities’ argues that what is needed to take all these efforts further is an ongoing virtual infrastructure and a community of practice: a network of scholars committed to using a Virtual Research Environment for their research including a small part-time team to lead it. So far 16 academic researchers from various European universities expressed a strong interest.

Lena Stanley-Clamp

Coordinator, Judaica Europeana

Director, European Association for Jewish Culture