Derived variables

Derived variables ... what are they?!

So what are 'derived' variables?  They are variables that you create by calculating or categorising variables that already exist in your data set.  An example of a derived variable might be Income Categories, that you would calculate for all of your participants using an existing continuous variable Income.

In this section, we are going to have a go at creating two different kinds of derived variables.  The first will be calculating a new variable from existing data.  The second will be creating a categorical variable from a continuous variable.

For this exercise, we are going to use income data from the 2016 Health and Society Health Survey to calculate income categories.

STEPS:

1. Open the 2016 Health and Society Health Survey Data.

2. Find the variable that represents monthly income.  We are going to calculate a new variable, annual income, from this existing variable, and then categorise the annual income data into income categories.

The income categories we are going to create are as follows:

1: $0

2: $1 to $10,000

3: $10,001 to $50,000

4: $50,001 or more