DDI Lifecycle: Moving Forward (Part 2)

Motivation

The DDI (Data Documentation Initiative) metadata standard, created in 1995, has in recent years become relevant to new user groups, including the official statistics and medical research communities. In order to respond to these new users, DDI is developing a model-based specification that can be expressed in XML Schema, RDF/OWL Ontology, relational database schema, and other languages. Such a data model will make it easier to interact with other disciplines and other standards, to understand the specification, to develop and maintain it in a consistent and structured way, and to enable software development that is less dependent on specific DDI versions.

In 2012 a group of invited experts launched the development of the model-driven specification at Schloss Dagstuhl. This work had three components – substantive content for the model, modeling principles and process, and bindings to other standards – and resulted in an internal paper shared among participants to ensure that all had a common understanding of the work. Work has continued on all fronts since the 2012 meeting.

Goals

The 2013 Dagstuhl workshop will extend and build upon progress made during the year to develop and implement the model in a community-driven way. This enables a distributed development effort, with different groups able to work on parts of the model somewhat independently. The stages in the process include a first stage in which domain experts do simple modeling using forms to express the normative aspects of their piece of the model, with output consisting of a useable UML representation plus a Word document or PDF. The goal is to define scope, structure, and documentation. In the second step the output form developed by domain experts flows into a technical review made up of two components: the technical team who will make use of the output and an editor. There is also a template for system binding to other expressions like XML. The output of this step is technical specifications -- UML and XML schema for publishing. The third step is implementation, and the actors are the community. There will be a reference implementation for beta-testing and the community will provide feedback. This technology preview will permit the DDI Alliance to actively engage with other standards and groups and bring them into the community and the conversation.

Expected Results

The 2013 workshop may include activities from all three stages and will bring in expertise from new communities. This workshop will provide a forum for interested participants with both a substantive and technical focus to contribute to a re-envisioned model-driven DDI specification. Deliverables from the workshop will include drafts of the model and its documentation, which will then be made available for public review, and mappings to other standards.