Field Level Comparison - spreadsheet showing differences between DDI-L 3.3 and DDI-L 4.0
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The content will be the same as version 3.3 but expressed in a technical structure that supports more flexibility and multiple syntaxes
Express content in multiple bindings/representations: XML Schema, RDF/OWL, JSON, UML and possibly others
Move to an automated production process that will expand our ability to support and test new content and work in a more iterative manner
Flatten the model to support full serialization of objects (objects can be published separately) and compiled in sets of objects that describe broader coverage (collections of concepts, study unit information, data collection instruments, etc.)
Modify the structure of DDI-L 3.3 to:
generalize XML centric content (example - xs:choice)
consolidate physical structure descriptions and rename objects as needed to addresses duplication of names within multiple namespaces
simplify identification and reference information to allow required content to be expressed in the model and syntax specific content to be added programmatically during the building of the outputs