Data Documentation Initiative
Wendy Thomas
University of Minnesota
The Data Documentation Initiative (DDI) is a standard developed by the international social science archival and data community to capture metadata on social science data files. Early versions of DDI covered simple surveys (DDI 1.0) and reflected the common structure of a code book including information on the background of the study, methodology, and a data dictionary. DDI 2.0 expanded to handle aggregate data through the addition of nCubes, a matrix structure consisting of dimensions as described by variables, allowing for the use of common dimensions by multiple nCubes. DDI 3.0 currently in a Candidate stage, represents a major change from the preceding versions. the primary change is a shift in focus from an archive-centric static codebook to encompassing the lifecycle events in data creation, organization, preservation, use and repurposing. The coverage has expanded to include more complex data types including series and complex files systems One of the goals in this process was to continue the progress of DDI towards a more machine-actionable structure. The intent of this shift was to both collect metadata at the point it occurred and then use it to inform the subsequent processes of data collection, variable construction, identification, acquisition, analysis, and application.
In developing DDI 3.0 care has been taken to align the contents and structure so that it supports related standards, allowing smooth interaction with geographic standards, bibliographic standards such as Dublin Core, concepts and data item structures (ISO/IEC 11179), mapping to other aggregate data formats (SDMX) and comparability with an SDMX registry, as well as keeping in mind the construct of METS and other packaging structures for transporting metadata and data. Although still in its Candidate stage, the promises of the new DDI standard has encouraged the development of new tools and an expanded group of users. This session will provide background and information on the specification and discuss its relationship to other standards, and support for registry work.