DDI - Data Documentation Initiative

A widely used, international standard for describing data from the social, behavioral, and economic sciences. Two versions of the standard are currently maintained in parallel:

  • DDI Codebook (or DDI version 2) is the simpler of the two, and intended for documenting simple survey data for exchange or archiving. Version 2.5 was released in January 2014.
  • DDI Lifecycle (or DDI version 3) is richer and may be used to document datasets at each stage of their lifecycle from conceptualisation through to publication and reuse. It is modular and extensible. Version 3.2 was published in March 2014.

Both versions are XML-based and defined using XML Schemas. They were developed and are maintained by the DDI Alliance.

Extensions

CESSDA MLI - Council of European Social Science Data Archives Minimum Level of Information

A common base profile of DDI for use by the member archives of CESSDA.

GSIM - Generic Statistical Information Model

A reference framework that provides a common terminology acroos and between statistical organisations; aligns with DDI and SDMX.

Tools

DDI on Rails

Server-side software for building a data portal, with a particular focus on survey datasets. It uses DDI to provide access to the data at the level of concepts and variables. For an example of it in use, see the SOEPinfo data portal.

DDI Tools

The Data Documentaion Initiative website's list of tools to implement the DDI standard.

DdiEditor

DdiEditor is a DDI-Lifecycle Editing Framework developed by the DDA - Danish Data Archive.

Geodoc Metadata Editor

The Geodoc metadata editor tool allows users to create, validate, edit and export geospatial metadata records. It also supports the creation and export of metadata records as XML output files compliant with a number of standards, including UK AGMAP 2.1, ISO 19115, FGDC, DDI, and Dublin Core.

Use Cases

CESSDA Catalogue

Provides a seamless interface to datasets from social science data archives across Europe using the CESSDA MLI profile of DDI.

DDI Projects

The Data Documentation Initiative website's list of projects adopting or encouraging DDI as a standard.

DDI Use Case Literature

Links to DDI 3 use case papers, which were the outcomes of a workshop held at the Schloss Dagstuhl - Leibniz Center for Informatics in Wadern, Germany, November 2-6, 2009.

ICPSR - Inter-university Consortium for Political and Social Research

A data archive providing leadership and training in data access, curation, and methods of analysis for the social science research community; all metadata conforms to the DDI standard.

The Institution for Social and Policy Studies (ISPS) Data Archive

Provides members of the scholarly community with access to files associated with scholarly studies for the purpose of replication, for all studies conducted by ISPS-affiliated researchers. ISPS metadata records conform to DDI requirements and include a minimal set of Dublin Core metadata elements.

UKDA - UK Data Archive

Curator of the largest collection of digital data in the social sciences and humanities in the United Kingdom, the archive uses DDI as the basis for its catalogue records.