Section author: Laiton Hedley

Computed Variables

Use Computed Variables to create new columns of data by performing calculations on existing columns. For example, you can transform responses into z-scores or compute a total score by summing several survey items.

You can create formulas using existing column names and functions, such as:

  • Z(response)

  • Q1 + Q2 + Q3 + Q4

Adding a Computed Variable

  1. Click the Data tab in the ribbon.

  2. Click the Add button.

  3. Select Append (or Insert) under Computed variables. A new column will appear in the dataset.

Configuring Your Variable

Once you have added a variable, you can configure it using the variable editor. To open the editor, double-click the column header or click Setup in the Data tab.

The jamovi variable editor showing the configuration for a computed variable.

In the variable editor, you can:

  • Name your variable: Type a meaningful name in the top box.

  • Add a description: Provide more context in the description field.

  • Create a formula: Type your formula directly into the formula box.

  • Use the function list: Click the small fx button to see a list of available functions and variables. Double-click any item to insert it into your formula.

For a full list of what you can do with formulas, see the List of Functions.

Example: Sum Score Across Survey Items

Suppose you have three items from a survey scored on a 1–5 Likert scale and you want a single overall score per participant. Add a computed variable called Total_Score and use the SUM() function:

SUM(Item_1, Item_2, Item_3)

Table 6 Sum score across three items

Item_1

Item_2

Item_3

Total_Score

4

5

3

12

2

3

2

7

5

4

5

14

For more examples — including reverse scoring, z-scores, and outlier exclusion — see the Common Data Recipes.

When to Use Computed Variables

Computed variables are ideal for one-off calculations. However, if you need to apply the same transformation multiple times (for example, reverse scoring ten different Likert items), creating a separate computed variable for each can be tedious.

In those cases, use Transformed Variables instead. They allow you to define a single rule and apply it across as many columns as you like. They are also the best choice for “if-then” recoding.