A Simplified Regression Formulation of Tukey's Test.
A simplified regression approach is used for Tukey’s test for multiple comparisons. By constructing k - 1 regression equations (where k is the number of means) in such a way that each mean is being compared to every other mean, the computed t-values that result from testing the significance of each regression weight can be compared to a modified value (q)/√2 from the studentized range statistic.