Thursday 25 April 2013

How Ancient History Encyclopedia linked up with Pelagios

We're back for some information on how we linked Ancient History Encyclopedia to Pelagios. I hope that this can be of help for future websites that join this excellent project.

First of all, we need to explain how AHE works. The website is entirely based on tags / keywords. Each tag has one (and only one) definition associated to it, and many possible articles, illustrations, or timeline events. It is possible --and indeed necessary for the website to work properly-- that articles, illustrations, and timeline events are linked to many tags. An article on "Trade in Ancient Greece" would be tagged with "Greece", "Economy", "Trade", "Colonization", and it would subsequently be listed under all those tags' pages.

Now the initial idea was easy: Let's link up every geographical tag of ours (cities, countries, regions) to its equivalent location in Pleiades. We've got 2,400 tags, and we expect to have many more in the future, so we didn't want to do this all by hand. Instead, we wanted something future-proof, that would notify us automatically of possible matches between tags and Pleiades locations.

Every day, we automatically import the Pleiades database of names, their respective location IDs and their locations and mirror it in our database using a cron job. We wrote a nifty little PHP function that converts the Pleiades data to a PHP array -- feel free to use it.

In our editorial team's interface we have a page that automatically tries to find possible matches between Pleiades place names and tags on AHE. For links, we only look at those tags which have a definition -- after all we only want to link up content that is of use to potential readers, not empty tags. Editors can then review the link suggestions and either approve or reject them. That way, we already found most of the links between our datasets.

Suggestion from the automatic linking script

Then there is the problem of links that aren't found by our automatic matching script. For example, on AHE the tag is called "Greece" whereas on Pleiades it's known as "Hellas". Another example would be "Mediterranean" on AHE is known as "Internum Mare" at Pleiades. No script can figure that out!

For those cases, we added another functionality to our tag editor form: Our editorial team can simply search the Pleiades DB mirrored on our server for links, for each tag. An editor could for example see the tag "Greece", notice that it's not linked to Pleiades, open the linking form for the tag Greece and manually search for "Hellas".
Tag listing for editors (2nd last column is the Pleiades link)
The search will give exactly the same type of results as the automatic linking does above, with a map to help the decision-making.

When a tag is linked, we write the Pleiades ID into a newly-created field in that tag's entry in our database (hoping that Pleiades will never change tag IDs).

Now it's time to deliver all this data in a format that Pelagios can understand. We have another script that goes through all the linked tags and fetches their respective definitions, as well as all articles and illustration that are linked to them in our database. Then we output each tag definition as Turtle/RDF in the Pelagios format, linked to a specific Pleiades ID. All articles and images associated with that tag are also output for that Pleiades ID. The final result looks like this. Notice that while each definition only occurs once (one definition per tag), articles and images can appear multiple times, linked to multiple tags (as one article or image is linked to many tags).

Personally, I find that Turtle/RDF is somewhat mindboggling and not exactly easy to understand (I'm not a professional programmer), but with the excellent help of Simon Rainer, Elton Barker, and Leif Isaksen we managed to make it work and validate. Thanks a lot guys... we couldn't have been able to do it without you!

We then submit the generated file to Pelagios (in the next version of Pelagios it'll be imported automatically on a regular basis).

I hope that this was helpful or at the very least interesting to anyone who is looking to link up with Pelagios. If your site is similar to ours, do feel free to drop us a line on {editor AT}! We're always happy to help!

Monday 8 April 2013

Ancient History Encyclopedia joins Pelagios

We are happy to announce that Ancient History Encyclopedia is joining the Pelagios project. Ancient History Encyclopedia is a non-profit digital humanities company with the aim of providing reviewed ancient history information on the web. All content is submitted by volunteer historians, authors, and enthusiasts and is reviewed by our editors before being published. We strongly believe in open access education, which is why all our content is free and available under a creative commons license.

Our mission is to make people interested in ancient history; we want to engage our global audience, by not only presenting the facts but also by doing it in an interesting way. We believe that "story" is a key component in the word "history", and we aim to convey in all our published content our belief that history is the greatest story ever written.

Despite being a story, history is not linear (as it is taught in most school coursebooks), but rather a very parallel type of story, where everything is interlinked. This is why digital media are much better-suited to history education than books of the dead-tree type (which we still love, of course). At AHE pieces of information are tagged and shared across different but related subjects, and each page is built automatically, taking precisely the information that is relevant for that subject from our database of definitions, articles, events, and maps.

Interactive Map of the Ancient World (WIP)
We adhere to academic standards when it comes to research and citations, but our readership is far more diverse than that of an academic publication. While we love pointing to new research, we mainly publish definitions and articles presenting the ancient past along lines commonly-accepted enough to enable a student to reference them in coursework and for an instructor to accept them without question.

Many high schools and undergraduate college courses around the world point to AHE in their reading lists or use it for course material. Our mission is to let everyone learn about ancient history in an engaging and easy-to-understand way. We want our readers to get excited about ancient history, and then we want to point them to the more detailed, academic, or original sources (both on our site and across the internet).

Joining Pelagios is simply the next logical step: The more history we manage to link together, the more our readers can "dig deeper" and get lost in ancient times. The easier it is for students to find the vast amount of material that all Pelagios contributors have assembled, the better. We are very excited to be part of the vast network of data coming from high-quality websites and established institutions alike!

New Pelagios Partners: DM Project

The DM Project is very excited to partner with Pelagios in its upcoming developmental work!

DM is an on-line environment that allows users to easily assemble collections of images and texts for study, produce their own rich data, and publish digital resources for individual, group or public use. At its most basic, DM is a tool for linking media - a suite of tools that enables users with little technical expertise to mark regions of interest in manuscripts, print materials, photographs, digital texts, etc. and provide searchable annotations on these resources and the relationships among them. A user may create links between any combination of resources (images, texts, and selected regions of images or texts as marked out by a user). The most common is a link from a textual annotation to the image, text, or selected region it describes, but a single annotation may also reference (e.g., for comparison) selections from several images and/or texts. Today, DM is being used by a number of projects, from long-term scholarly initiatives, to collaborative research, to individual scholarship. In addition to such use-cases, we are collaborating with the Stanford University’s Digital Medieval Manuscript Initiatives and the SharedCanvas project, as well as other partners and projects at Stanford, the University of Toronto, Johns Hopkins University, Yale University, the British Library, St. Louis University, and Los Alamos National Lab, among others.

Our current phase of development is funded by a multi-year Digital Implementation Grant from the NEH. During this work, we will be focusing primarily on the ability to: A) create and manage collections of images and texts; B) add the ability for users and groups in order to create, track and organize work by different collaborators within a working group; C) easily "roll out" the linked and annotated data created within the DM environment to a wide array of standard publishing formats (e.g. for automated and updatable display within Omeka, MediaWiki, and similar platforms); and D: developing Virtual Mappa with the British Library, a pilot environment of historic maps hosted by multiple repositories, where users may create linked environments of annotations for individual, collaborative, and educational purposes.

In late April / early May 2013, DM will be rolling out a new version of the resource, with new features for working with multiple collections of on-line images, as well as improved functionality for managing workflow, navigation and annotation. A sneak peek at some of the functionality is available on our project website, which also contains information about the project's history, its partners, and its current goals:

Martin Foys & Shannon Bradshaw


DM Project

Co-Directors:  Shannon Bradshaw, Associate Professor of Computer Science &
Martin Foys, Associate Professor of English (Drew University)