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Variables contain data constructed from other questions or variables. There two types: with responses, and with values.
All entries are stored in the Project master (QDF) file.
Variables can be added from the Main window, by using the [Insert] menu, toolbar button, or the context menu (right click).
Details about the new variable are entered in the Entry details window. This window is used to add and update all entries, except program entries. For variables, see Entry details, variable.
You do not need to close the Entry details window after each new entry is inserted because there are toolbar buttons to add more new entries.
The order of entries in a project is very important, see Reference Manual, Entry rules, Entry order.
See Project components for a brief introduction to variables.
See also Grid variable pair for special variables created for Grid tables.
The administered questionnaire mainly comprises these entries:
•Question entries that define the questions to be asked and response lists for closed questions
•Filter entries that define subsets of the data and that can be applied to questions so that not all questions are seen by all respondents
Response filters can also be applied to questions with response lists so that not all responses are available for all respondents.
There are times when the above entries (questions and filters) are not sufficient to complete the whole process. For some projects additional entries are needed:
•Variable entries that perform intermediate steps or calculations
•Program entries that randomise the order of entries
Variables are also used in analysis reports to combine data in various ways.
There are two main types of variable:
•Variables with a response list (single-coded and multi-coded)
•Variables with a calculated value (integer and float)
The way these two types of variable are defined is exactly the same for all these purposes:
•Routing during an interview
•Consistency checking during an interview
•Making response filters during an interview
•Combining questions for analysis
•Calculations for analysis