Server User Guides > Survey Tabulation > Understanding variables
 
Understanding variables
Variables are the building blocks that you use for building tables and defining filters. In a data set based on a questionnaire or survey, a variable generally corresponds to a question or a part of a question, and records the question text and stores one answer, or set of answers, for each respondent who answered the question. However, some variables store other information, like a serial number or weighting details.
In a data set that is not based on a survey, the variables store characteristics that have been measured. The basic unit of analysis for which measurements are taken is called a case. In a data set based on a survey, a case generally corresponds to a respondent.
Variables fall into a number of different groups, based on the type of data the variable stores, the type of question the variable is based on, and the way the variable is used. This section provides an introduction to the main types of variables.
Variables are shown in The variable list, which is built into the Define tab and the Edit Filter and Edit Category dialogs. An icon beside each variable indicates its type. For a list of variable types and their icons, see Variable icons.
UNICOM Intelligence Reporter - Survey Tabulation reads the definitions of the variables from the metadata, which is often in the form of a questionnaire definition (.mdd) file. The metadata defines the structure of the data and stores question and category texts in one or more language. UNICOM Intelligence Reporter - Survey Tabulation only accesses the stored responses when necessary (for example, when you populate your tables). The response data is called case data.
See
Categorical variables
Text variables
Numeric variables
Boolean variables
Loops and grids
Blocks and compounds
Derived variables
Axis expressions
Variable icons
System variables
Variable data types