Markup Examples

The flexibility of DDI allows for many different applications and uses. See below for a selection of markup examples demonstrating a variety of implementations.

DDI Codebook

Name DDI Product Description
ICPSR 4245 Codebook for American National Elections Study DDI Codebook 2.5

Study level information originally created in NESSTAR using version 1.2.2 and updated to version 2.5

Multilanguage Codebook DDI Codebook 2.5

Study level documentation in French and English: 

Cohorte blessures scolaires en fonction du genre / School-Related Injuries as a Function of Gender

NHGIS 1990STF1 Codebook DDI Codebook 2.5

This codebook of the US 1990 Census of Population and Housing Summary Tape File 1 includes source information and uses the structures for nCubes and locMap description of the data store. The codebook was produced for the IPUMS National Historical Geographic Information System (NHGIS)

ICPSR 2825 DDI Codebook 2.1

Current Population Survey, 1999: Annual Demographic File (ICPSR 2825)

This is an example using the Version 2.1 DTD. The ZIP file contains the XML instance, an HTML transformation of that file, the PDF version based on the transformation, the orginal ASCII text file and PDF file for the codebook.

ICPSR 7728 DDI Codebook 2.1

Euro-Barometer 10: National Priorities and the Institutions of Europe, October-November 1978 (ICPSR 7728)

This is an example using the Version 2.1 DTD. The ZIP file contains the XML instance, an HTML transformation of that file, and the orginal ASCII text file for the codebook.

DDI Lifecycle

Name DDI Product Description
DASHISH example of questions and related content as fragments DDI Lifecycle 3.2 Markup examples produced by the DASHISH (Data Service Infrastructure for the Social Sciences and Humanities) project The example use the new Fragment Instance expressed in three files: • Question Item A (file b1) • Question Item B (file b9) • Control Construct (file d39)
ICPSR 2079 Variable Descriptions DDI Lifecycle 3.2 Variable descriptions for ICPSR study 2079 – “CBS News/New York Times Monthly Poll #1, September 1995” – converted to 3.2 from DDI 2.1 with Colectica Designer, a tool for DDI metadata and survey design. The file uses the new FragmentInstance structure.
Study Level Metadata Example DDI Lifecycle 3.2

This example covers just the study level information (no Variable or Questionnaire detail) but provides an extensive example of the use of 1) Organization, Individual, and relationships between them, 2) Topical Coverage, and 3) Archive information on access and lifecycle events. This example is multilingual. The example treats the study (ALLBUS/GGSS 1980-2016) as a subgroup of a larger unspecified group.

Archive Example DDI Lifecycle 3.3

An example of Archive content covering a small collection of items, access information, and lifecycle information related to the aquisition, documentation, and integration of an item into the archive.

Data Capture Development DDI Lifecycle 3.3

This example shows the use of the Data Capture Development objects including the documentation of development activities such as translation and review activities. In addition to tracking these specific activities the example illustrates the means of linking a question or measure to the development activities which resulted in the final form of the question/measure used.

Data Capture Development DDI Lifecycle 3.3

Example of use of data capture development content to describe the development of a question and the use of a question in a questionnaire. Includes Development Plan, Development Implementation, Development Activity, and Development Results. 

Date Expressions DDI Lifecycle 3.3

Example of the different types of date expressions including a single date, full date range, range with an unknown start date, and range with and unknown end date.

Input, Output, and Binding DDI Lifecycle 3.3

Input Parameters, Output Parameters, and Binding support passing data through a process. 

This is a very detailed example walking through all the control constructs, questions, dynamic text, and control constructs. In general usage bindings out parameters and bindings would be noted at the highest discrete level such as the Question Construct for the data captured by a Question Item. Identification and binding at this level keeps the question reusable across various uses in a questionnaire.
Note Example DDI Lifecycle 3.3

Note is designed to be an inherent part of the DDI passing along with a DDI object over its lifetime. It is not intended to replace formal extension mechanisms. Formal extension should be used whenever a locally used object needs to be added to the schema. However, run-time extension needs may arise and Note can be used to capture the required metadata and associate it with the appropriate object.

This example shows a production process note,  a work-around, and a proprietary content note.

Quality Statement Example DDI Lifecycle 3.3

Quality Statements and their declaration in Collection Event, Physical Instance, Archive Specific, Quality Statement Scheme, and Data Appraisal


Question Types DDI Lifecycle 3.3

Example of Question Scheme, Question Item, Question Grid, Question Block with related schemes

Representation Types DDI Lifecycle 3.3

Examples of various Representations in the form of Managed Representations, new geographic code representations with restrictions, and the use of Representations used expressly as Response Domains (geographic, distribution, ranking, location, and nominal).


Represented Variable Example DDI Lifecycle 3.3

Represented Variable and use by a Variable with restrictions on the Universe in two different ways; restricting the geographic coverage, and restricting the age of persons covered by the variable.


Sampling Example DDI Lifecycle 3.3

Example of the use of sampling content to describe the sampling plan, sample frame used, implementation of the sampling plan, and resulting sample details.

Summary Statistics DDI Lifecycle 3.3

Example of Statistical Summary found in Physical Instance. The example includes summary statistics (variable level) weighted and unweighted as well as filtered and unfiltered variable and category statistics.

Weighting Example DDI Lifecycle 3.3

An example of weighting information including methodology, description of a weighting process, usage guide, and the ability of a variable to use this information to reference a weighting process.