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What's New

DDI4 Sprint to Take Place in Minneapolis in May 2015

The Minnesota Population Center (MPC) at the University of Minnesota will be the setting for the next DDI4 sprint, the seventh in a series of sprints focused on development of a model-driven DDI specification (DDI4). The sprint will take place Monday-Friday, May 25-29, at the MPC with a set of invited participants in attendance.

More information on the sprint is available on the DDI Moving Forward wiki at:

Information on previous sprints is available here:

SDMX Releases Validation and Transformation Language (VTL) for Review

A dedicated task-force of the SDMX Technical Working Group (TWG) submits the new specification of a Validation and Transformation Language (VTL) for public review. The review period extends until 8th November 2014 in order to allow time for consolidation of a final version at the end of 2014. Feedback is welcome.

At the end of 2012, the SDMX Secretariat requested the TWG to start a new work package on “Expressions and Calculations” aimed at allowing the definition and the exchange of validation and transformation rules, based on the generic framework for defining mathematical expressions already existing in the SDMX information model. To make such framework fully operational, a standard language for defining validation and transformation rules (set of operators, their syntax and semantics) should be adopted, while appropriate IT formats for exchanging such rules – and web services to store and retrieve them – should be designed.

The intention is to provide a language which is usable by statisticians to express logical validation rules and transformations on data, whether described as a dimensional table or as unit-record data. Although a work-product of SDMX, the VTL language is based on the GSIM data model and should be usable with other standards as well. The present draft for public review also provides (in its part 1) a formal description of data validation at business level against which information models can be mapped.

VTL – part 1: Validation and Transformation Language (General Description)

VTL – part 2: Validation and Transformation Language (Library of Operators)

Please send your comments to the SDMX Technical Working Group (SDMX-TWG) at Each email message should contain only a limited set of numbered – and possibly homogeneous – comments and should contain the elements indicated in the attached comment log.


Review of RDF Vocabularies Under Way

Announcement of the public technical review on draft versions of the RDF vocabularies

DDI-RDF Discovery (Disco), Physical Data Description (PHDD), and Extended Knowledge Organization System (XKOS)

DDI-RDF Discovery (Disco)

Disco is designed to support the discovery of microdata sets and related metadata using RDF technologies in the Web of Linked Data.

Physical Data Description (PHDD)

PHDD describes existing data in rectangular format and CSV format (character-separated values).

Extended Knowledge Organization System (XKOS)

XKOS leverages the Simple Knowledge Organization System (SKOS) for managing statistical classifications and concept management systems, since SKOS is widely used.

These vocabularies can be used in the context of Linked Data and statistical classifications. We are interested in comments and any type of critique regarding the vocabularies and their possible interplay with other vocabularies. We would like to achieve robust versions of the vocabularies on the basis of this technical review and then publish them as specifications of the DDI Alliance.

Review until: July 6, 2014

Response email address:

Organization: DDI Alliance (Data Documentation Initiative),

For more information see the RDF vocabularies review page.

Call for Papers: 6th Annual European DDI User Conference (EDDI14) DDI - The Basis of Managing the Data Life Cycle

Submission Deadline:     September 7, 2014
Place:                              London, United Kingdom
Date:                               December 2 - 3, 2014
Host:                                IOE - Institute of Education, University of London
Conference web page:

EDDI14 is organized jointly by the IOE - Institute of Education, University of London, GESIS - Leibniz Institute for the Social Sciences, and IDSC of IZA - International Data Service Center of the Institute for the Study of Labor.

The meeting will bring together DDI users and professionals from all over Europe and the world. Anyone interested in developing, applying, or using DDI is invited to attend and present.

Call for Papers

We are seeking presentations, talks, papers, posters on all things DDI:

  • Case Studies
  • Mature implementations
  • Early Implementations
  • Interplay of DDI with other standards or technologies
  • Projects in early phases in which DDI is under consideration
  • Critiques of DDI

We strongly encourage papers in different areas to ensure that a broad balance of topics is covered which will attract the greatest breadth of participants, and we encourage conference participants to propose presentations, papers, and posters that would be of interest to themselves and other attendees.

The topics of the conference include, but are not limited to:

  • Infrastructure for Data Collection, Research, and Archiving
  • Reusing and Sharing Metadata
  • Official Statistics
  • Open Data and Linked Open Data
  • Privacy and Access Control
  • Data Harmonization
  • Incentives to Document Data
  • Metadata versus Data and Related Ethics
  • Software / Tools


Proposals are welcome for:

  • Regular presentations
  • Short presentations
  • Full papers
  • Plenary presentations
  • Complete sessions
  • Tutorials and workshops
  • Posters and software demonstrations

If you are interested in submitting a proposal, please use the online submission system of the conference. The deadline for submissions is September 7, 2014. Please have a look at the Call for Paper page for further details. Please consider to indicate the availability as reviewer as well.

General Information

For more information about the conference, see the conference web site at

For questions or any other correspondence regarding EDDI14, please send an email to

Last year’s presentations and posters are available at the EDDI13 website, full papers at a web page of the DDI Alliance Working Paper Series.

For more information about the EDDI conference series and details on the previous EDDI conferences, look at

Kind regards,
Joachim Wackerow on behalf of the EDDI14 program committee

Opportunity for New DDI Trainer

For the past eight years, GESIS-Leibniz Institute for the Social Sciences has organized intensive five-day DDI training workshops at Schloss Dagstuhl in Wadern, Germany. (Dagstuhl is a computer science research center that focuses mainly on a highly acknowledged seminar series.) This year’s training workshop will take place on October 13-17, 2014.

Joachim Wackerow (GESIS) leads the training workshop along with co-trainers Arofan Gregory (Metadata Technology) and Wendy Thomas (Minnesota Population Center). To plan for the workshop, Arofan and Wendy spend the week before the workshop in Mannheim (one of the two GESIS locations) where the three trainers prepare the syllabus and the schedule for the upcoming workshop. This has worked well and has been a successful model.

In an effort to diversify and supplement the pool of qualified DDI trainers and to start to build the next generation of instructors, this year GESIS together with the Dagstuhl trainers is offering a "train the trainer" opportunity, funded by the DDI Alliance. This will enable a new trainer to attend the preparation week in Mannheim and the workshop at Dagstuhl. The goal is that this person could then conduct similar training in the future either alone or with others.

The Alliance will fund the cost of the new trainer's travel, accommodation, and food for two weeks, and will provide a stipend of Euro 1000.

We are looking for a highly motivated individual who has an interest in DDI and in training others in its use. This person will need to be available for the full two weeks (Week 1 in Mannheim, October 6-10, and Week 2 at Dagstuhl). 

To apply for this opportunity, please send a letter of interest, a resume or set of qualifications, and a vision for future DDI training to the DDI Alliance Director by June 22, 2014. The trainers will select a person for the position and he or she will be informed by July 7.

Joachim Wackerow

Mary Vardigan

DDI Alliance Members and Scientific Board to Meet in Toronto on June 2

The DDI Alliance will hold its Annual Meeting of Members in Toronto on Monday, June 2, 2014, in advance of the annual IASSIST Conference. The IASSIST program will feature several sessions related to DDI.

NADDI Conference to Take Place in Vancouver, March 31-April 2, 2014

Research data management has become an important global issue as funding agencies, publishers, and disciplines increasingly require the sharing of publicly funded data.  The Open Data movement treats curated data as a valuable resource available to support new research with the potential for new discoveries. Furthermore, the expectation that research findings can be replicated is pressuring researchers to make their data understandable and useable by others. Both the replication and reuse of research data is highly dependent on properly documented data. The Data Documentation Initiative (DDI) provides two structured metadata specifications for describing the content and context of data about individuals or organizations (microdata) in the health, social, and behavioural sciences. This community-maintained standard for microdata is internationally recognized as a best practice in preparing, sharing, and preserving data.

Interested in learning more? Please join us in Vancouver for the second North American DDI Users Conference, to be held March 31-April 2, 2014. Organized by the University of British Columbia, Simon Fraser University, University of Alberta Libraries, and the Institute for Policy and Social Research at the University of Kansas, the meeting will take place at at the Harbour Center, Simon Fraser University, with the theme"Documenting Reproducible Research." 

The Keynote Speaker for the conference is Ann Green. Ann is an independent research consultant focusing on the digital lifecycle of scholarly resources, including their creation, delivery, management, long-term stewardship, and preservation. She has significant history and experience with the DDI, serving on the original DDI committee in 1995 and coauthoring the first DDI specification. 

The conference will feature training sessions on Monday, March 31, and an opening reception that evening. Monday's training will cover an introduction to DDI in the morning and the use of DDI to document health-related data in the afternoon. Conference sessions focus on a wide range of innovative topics and projects -- from field-testing multilingual clinical assessments using DDI to chaining together existing DDI tools to documenting qualitative data.

We hope to see you there!

EDDI 2013 Draft Program Available and Registration Open

EDDI13, the 5th Annual European DDI User Conference, will take place on December 3-4 2013 in Paris. The conference is hosted by Réseau Quetelet, the French portal for data in the humanities and social sciences.

The conference will open on Tuesday, Dec 3rd, at 9:00am and close on Wednesday, Dec 4th, at 5:30pm.

Tutorials (included in the conference fee) will take place on Monday, Dec 2nd, at 2:00 pm - 5:30 pm.

A schedule overview and draft program are available at: The detailed program is in preparation.

Registration for participants and accommodation bookings are open. Please have a look at: and

Please note following important details:

The deadline of the early bird fee is open till October 27, 2013. The reduced rate of the main hotel is available till November 3, 2013. The conference has a maximum number of participants of 90 people.

Date Set for 2014 DDI Alliance Meeting of Members

The 2014 Annual Meeting will take place in Toronto, Ontario, Canada, on Monday, June 2, 2014, before the IASSIST conference, which will be held on June 3-6, 2014.

Second North American DDI User Conference to Take Place in Vancouver

The second annual North American DDI User Conference will take place at the Harbour Centre in Vancouver, Canada, on April 1-2, 2014, with workshops taking place the day before on March 31. Simon Fraser University, University of British Columbia, and University of Alberta are co-hosts for the event. The program and Web site are currently being developed. If you would like to participate, please send email to Larry Hoyle