How to Specify Columns to be Compared in a Table

By default, Column Comparisons test all non-NET categories within a row and within a Span. This article describes how to specify which columns you want to compare. Any changes you make to the specific columns tested for a particular question will appear in all tables where that question is used in the columns. While this article focuses on the settings for the question in the Comparisons dialogue, you should also review other information in the Requirements section to ensure your other testing assumptions are in line with how you want to test.

This article covers how to:

Compare within spans including NETs
Compare custom columns within a span
Compare all columns
Compare custom columns on the entire table
Compare columns against the main NET

Requirements

A crosstab with multiple columns, without a Date/Time question in the brown dropdown. These examples use the following table:
Understanding how to set statistical assumptions. To do this on a project level, go to the Edit > Project Options > Customize > Statistical Assumptions tab. Otherwise, you can set this on one or more selected tables through Table Options > Statistical Assumptions.
Show Significance dropdown is set to Compare columns.
An understanding of the Statistical Assumptions > Column Comparisons > Overlaps setting, see Overlaps for more info. If changing to either Dependent or Independent, you will also need to change Statistical Assumptions > Test Type > Proportions/Means test to something other than Non-parametric.
An understanding of the Statistical Assumptions > Column Comparisons > Multiple Comparison Correction settings, see How to Apply Multiple Comparison Correction to Statistical Significance Testing.

Method - Compare within span including NETs

Because respondents in the NET column completely overlap with respondents in other columns, you will need to set Statistical Assumptions > Column Comparisons > Overlaps to either Dependent or Independent depending on what types of tests you'd like to run.
You will also need to change Statistical Assumptions > Test Type > Proportions/Means test to something other than Non-parametric. Click OK to close the window.
Right-click on a column header in the table and select Comparisons. (Note this can also be accessed by right-clicking on a header and going into the Table Options > Statistical Assumptions > Column Comparisons tab).
Check the Compare within spans > Include NETs box and click OK. Note, if you only want to include the NET on some of the spans, see the next section to compare custom within span.

Now you will see the NET columns are tested against the other columns within the span:

Method - Compare custom columns within a span

You can only customize testing custom columns within one span at a time. Right-click on the header of the span you want to change and select Comparisons. (Note this can also be accessed by right-clicking on a header and going into the Table Options > Statistical Assumptions > Column Comparisons tab).
Select Custom within span.
In the open text field, specify which columns to compare using the column names and /. To have multiple configurations, you can separate each test by a comma. So to test the Age columns custom where column A is only tested against the NET (D), but the other columns are all tested against each other, you would use:
A/D, B/C/D

You'll see something like this:

Method - Compare all columns

If your table has spans, follow the instructions in How to Compare Columns Across Spans.
If any columns have respondents that overlap, see the requirement above about confirming how to treat overlaps.
Otherwise, right-click on a column header and select Comparisons.
Select Compare all columns.
[OPTIONAL] Tick Include NETs if wanted. You will need to also complete steps 1 and 2 in Compare within span including NETs to change the overlaps setting if including NETs.
Click OK.

You'll see something like below:

Method - Compare custom columns on the entire table

If your table has spans, follow the instructions in How to Compare Columns Across Spans.
If any columns to test have respondents that overlap, see the requirement above about confirming how to treat overlaps.
Otherwise, right-click on a column header and select Comparisons.
Select Custom.
In the text field, specify which columns to compare using the column names and /. To have multiple configurations, you can separate each test by a comma. To test columns for each question against one another:
A/B, D/E/F