# Binary Variable

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Complicated Filters | |

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A *binary variable* is a variable that takes only two values, most commonly values of 0 or 1. Binary variables taking values of 0 and 1 are used as Filters and for other general analysis purposes (e.g., representing Pick Any questions. Any 0/1 binary variable can be created as a filter.

This page address binary variables that are created by either:

- Creating a Filter from the Cells on a Table
- Right-clicking on a variable in the Variables and Questions tab and selecting
**Insert Variable(s) > Binary - Complicated Filter**.

Links to other methods for creating Binary Variables are described at the bottom of the page.

## Defining a binary variable

Binary variables are defined using *Boolean Logic*. If the screen shows **Undefined Filter Term** you need to select one of the variables or questions from the list of **Variables and Questions**. To add another term, select something in the box at the top-right and press (otherwise, you will over-write anything already created).

## Buttons, options and fields

**Name** The name of the variable to be created.

**Label** The label of the variable to be created.

**Variables and Questions** List of variables to be used to construct the binary variable.

**Comment** Optional description.

**Contains** Rule determining how observations are to be selected.

**Values/Labels** Unique values of the variables and questions for use in construction of the variable.

- For Pick One and the variables in Pick One - Multi questions ,
*Values*contains a list of the different categories and**Contains'***gives a choice of**Any of*.**and**None of - For Pick Any questions,
**Values**contains a list of the different categories and**Contains**offers a choice of**Any of**,**All of**,**Only/exactly**and**None of**. - For Text and Text - Multi questions,
**Values**contains a list of the unique text values for the variable and the Contains box will have a choice of**Equals**and**Not equals**. - Numeric Questions and Date Questions,
**Contains**offers a choice of**Equals**,**Not equals**,**Greater than**,**Greater than or equals**,**Less than**,**Less than or equals**and there is a box in which you can enter a value. (The “value” for missing data is NaN; if using a Numeric Variable and you have not explicitly referred to it as NaN, any observations with missing values will automatically be assigned a value of 0 and thus not selected in the resulting binary variable.)

*Boolean operators*

**+**Adds a filter term.

**-**Removes selected filter term(s).

**AND**‘And’ logical operator.

**OR**‘Or’ logical operator.

**NOT**Logical negation. You may negate any existing term or operator using this button.

## See also

- See How to Compute Binary Variables for a list of alternative ways of computing binary variables.
- Multiple Response Data Formats