How to Band Numeric Variables using a Table

This article describes how to go from a numeric variable represented in aggregate on a table:

To a categorical variable showing numeric bands (e.g., 0, 2-5, 6-10, 12+) for analysis purposes:

Requirements

• A variable Structured as one of the following:
  • Numeric - they have a "2" next to them in the Data Sets tree:
  • A categorical variable structured as Nominal or Ordinal. If there is text involved with the value label (eg: 0 – Not at all likely and 10 – Extremely Likely are the endpoints of your scale). If using this type of variable, it is prudent to check the Values so that they align correctly with the labels. The Values button is just under the Structure dropdown in the object inspector as per the picture below. You don’t want a value of 1 ascribed to 0 - Not at all likely and so forth (it should be a value of 0). You should change it so that the correct value aligns with the label.
    

Method - Using Drag and Drop

1. [Optional] If your variable is Numeric, select the variable in the Data Sets tree, click Duplicate to create a copy of the variable. In the object inspector, change the Structure to be Nominal (or Ordinal). 
2. Drag your categorical variable onto the page to make a table.
3. Select the categories you want to band together (using Ctrl or Shift) and drag the stacked brick icon () onto the last number in the band until you see the word Merge appear.
4. From the toolbar, click Rename to give the banding a correct label.

Method - Using Combine

1. [Optional] If your variable is Numeric, select the variable in the Data Sets tree, click Duplicate to create a copy of the variable. In the object inspector, change the Structure to be Nominal (or Ordinal). 
2. Select all of the categories you want to band together (using Ctrl or Shift), and from the toolbar, go to Combine > As One Category to merge them into a single category.
3. From the toolbar, click Rename to give the banding a correct label.

   

CAUTION:

A drawback to using this method is that if you update your data file with fresh data (e.g., more respondents) then you may end up with a category that is not in a band. For example, if you band 1,2,3,4,6,7,9, and 10 into a band "1-10" using the drag-and-drop method and then update your data file, you may have new cases that provide a 5 or 8 score. These new values have not been included in the "1-10" band, and you’ll have to manually merge them in (by repeating the process above). To get around this, use either the R or JavaScript banding methods linked below.

Next

How to Band Numeric Variables Using R

How to Band Numeric Variables Using JavaScript