Added automatic builds
Each day a ZIP-file is created via cron.
The builds consist of XMI, XSD, DocBook, PDF and graphs in dot, svg and png.
Added basic validation for names
installed module for validation, some rules for object and package names have been defined.
Added help for creating and managing the model
Guidelines for naming and propeties.
Added stage-tagging for objects
Re-arranged "Status" and added field for Stage, filter added on objects page.
Changes for Datatype
Datatype taxonomy is replaced by a datatype content type, to create a new one go to /node/add/datatype. You can specify basic documentation of the datatype and specify enumerated values. A datatype must be placed in a package.

Welcome to the development platform for the next generation of DDI

The DDI Alliance is building a new model-based specification, for more information on the background to this see, the process and what we hope to achieve see the DDI Alliance website at

A site to hold discussions and further ongoing discussion is at


Methodology defines the design and process used within data collection, management, and use to achieve overall studies or specific activities such as sampling or weighting. A methodology in normally informed by earlier research and clarifies how earlier research methods were incorporated into the current work.

NOTE: This is initially being entered as a non-abstract object. If Methodologies becomes a pattern this class would act as the primary entry point of the pattern and be changed accordingly


Sequence of Classification Index Entries in a Classification Index.


Part-whole relation of Nodes in a Node Set.


Describes a series by providing citation information and coverage information.


Classes related to the information about a "Study" - an activity which produces data. These activities may be organized into larger activities "StudySeries". An example would be a longitudinal study in which each wave or phase might be documented as a Study and the whole documented as a StudySeries.


StudySeries describes a series and therefore collection of collection activities as instances of Study.


Study is the conceptual anchor for an individual collection activity resulting in a data set or data file. It can be both a part of a StudySeries as a wave etc. or an unrelated activity like a single survey project.


The number of characters by which a DataPoint is represented in a physical layout.


The pair of Instance Variables in a Record Layout which are being placed in a sequence.


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