DEFINITION of 'Scheffe's Test'
A statistical test that is used to make unplanned comparisons, rather than pre-planned comparisons, among group means in an analysis of variance (ANOVA) experiment. While Scheffe's test has the advantage of giving the experimenter the flexibility to test any comparisons that appear interesting, the drawback of this flexibility is that the test has very low statistical power.
BREAKING DOWN 'Scheffe's Test'
While pre-planned comparisons can be made using tests such as t-tests or F-tests, these tests are not suitable for post hoc or unplanned comparisons. For such comparisons, multiple comparison tests such as Scheffe's test, the Tukey-Kramer method, or the Bonferroni test are appropriate. The Scheffe test is named after American statistician Henry Scheffe.