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 Getting Started with the DDI
 Frequently Asked Questions (FAQ)
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 Document Type Definition (DTD)
 XML Schema (XSD)
 DDI Lite (Recommended Elements)
 Version Control for DTD
 Information on DTD Elements (DDI Tag Library)
 Mapping to Other Metadata Standards
  • Dublin Core
  • Recommended Fields (CESSDA) (PDF)
 Related Tools
  • Software/Tools
  • XML/XSLT

Technical Information

Version 3.0

The XML Schema files of DDI 3.0 are also available for online usage. See the DDI3 page for more information on Version 3.0.

Version 2.1

This page contains links to the codebook DTD, its structure, and other information on how it can be used.

Document Type Definition (DTD)

XML Schema (XSD)

DDI Lite (Recommended Elements)

Version Control for DTD

Archival DTDs and Schema can be found in the SourceForge.net >CVS repository by following any of the "Download" links above.

Information on the DTD Elements

This information is provided as instruction and support for those using the DTD or exploring its use in their markup efforts. Users should note that the Tag Library is an evolving document, and additional remarks, definitions, and examples will be added periodically.

The DDI Committee encourages researchers to use and evaluate the Tag Library and to send comments on their experiences to ddi@icpsr.umich.edu.

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