More on the means comparison with unequal variances problem.

Scheffe gave an exact solution to the problem of comparing two means from normal populations with unequal variances that is useful for general analysis of variance problems. The behavior of the usual t-statistic that assumes equal variances is contrasted to Satterthwaite's approximate t-statistic and Scheffe's method. An interesting relationship is uncovered between Scheffe's and Satterthwaite's solutions.