Introduction to Between-Subjects Analysis of Variance:
Preliminaries (4 of 4)
Next section: Two estimates of variance
This means that the
probability values computed in
an ANOVA are satisfactorily accurate even if the assumptions are violated. Moreover,
ANOVA tends to be conservative when its assumptions are violated. This means
that although
power is decreased, the probability
of a Type
I error is as low or lower than it
would be if its assumptions were met. There are exceptions to this rule.
For example, a combination of unequal
sample sizes
and a violation of the assumption of homogeneity of variance can lead to
an inflated Type I error rate.
Next section: Two estimates of variance