These are methods for identifying where differences are among treatment means. All work by comparing pairs of means. Results of such comparisons are commonly represented with letters "abc", for example T1 ab where any two means that do not share a common letter will differ at some significance level (eg P<.05). T2 and T3 differ, but T1 and T2 do not. Contrasts are a preferred alternative approach to identifying treatment differences. See a comparison of various mean separation methods. Visit the DAWG module Comparing Means for more details.

