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Which of the following regarding the assumption of sphericity is false? (Hint: Even very small departures from sphericity produce large biases in the F-test.)
Sphericity does not affect post hoc tests.
The effect of violating sphericity is a loss of power (i.e., an increased probability of a Type II error).
When sphericity is violated, we need to adjust the degrees of freedom for any F-ratios affected by the violation.
When sphericity is violated, the Bonferroni post hoc test can be used.
