If two sample levels are significantly different, the letter of the sample level with a smaller share of responses is placed into the comparison cell of the other level. An Uppercase letter indicates a stronger difference between levels than a lowercase letter. The default alpha level (significance level) for an uppercase letter is 0.05 and 0.10 for a lowercase letter. In Figure 4.5 the B indicates that there is a difference in the country of origin for Sporty and Family cars at the 0.05 significance level. The B is in the row for Family cars because the total responses for Family cars (155) is greater than the total for Sporty cars (100). The c in the Sporty row indicates that there is a difference at the 0.10 level between the country of origin when comparing Sporty to Work cars. The c is in the Sporty row because the total responses (100) is greater than the total responses (48) for Work cars.

Warnings for small counts are also included in the comparison cells. One asterisk indicates that the level has fewer than 100 responses and two asterisks indicate fewer than 30 responses. In Figure 4.5, notice that the row for Work has 48 total responses and is labeled with a single asterisk. You can change the alpha levels and warning counts in the Categorical platform preferences. For details about changing preferences, see Set Preferences.

SeeExample of Compare Each Sample with Comparison Letters, Example of Compare Each Cell with Comparison Letters, and Example of Mean Score with Comparison Letters.