The grouping information table highlights the significant and nonsignificant comparisons. The table includes the following information:

·    Method – the multiple comparison method used to construct the family of confidence intervals from which the grouping table is generated.

·    Comparisons – each grouping information table compares levels of one factor, or combined levels of multiple factors.

·    N – the sample size for each factor level.

·    Mean – fitted means sorted in descending order.

·    Grouping – contains columns of letters that group the factor levels. Levels that are labeled with an A are not significantly different from the control level. Conversely, levels that are not labeled with an A are significantly different from the control level.

To determine a likely range for the difference between two means, examine the hypothesis test results or the interval plot for differences of means.

For the salary analysis, comparisons were requested between the mean for the control level (subject 4) and the means for all other levels of the subject factor.

·    Subject 2 shares a grouping letter (A) with the control level. Therefore, subject 2's mean (2.80667) is not significantly different from the control level mean (2.84000).

·    Subjects 1 and 3 do not have a grouping letter. Hence, their means (2.15000 and 3.1133) are significantly different from the control level mean (2.84000). Teaching subject 3 paid significantly higher than the control subject while teaching subject 1 paid significantly less.