On the Sensible Application of Familywise Alpha Adjustment

This essay responds to Daniel O'Keefe's “Against Familywise Alpha Adjustment.” Whereas O'Keefe maintains that one should never attempt to control Type I error introduced when many statistical tests are conducted, this essay argues that alpha adjustment should be applied only in the narrowly circumscribed instance when the researcher wants to make a strong claim that there is no Type I error in a specific collection of tests.