This dataset contains information from a study of the effect of
sensory deprivation on people's alpha-wave frequency. Twenty volunteer
subjects were randomly divided into two groups.  Subjects in group A were
subjected to a 10-day period of sensory deprivation, while subjects in
group B served as controls.  At the end of the experimental period,
the alpha-wave frequency was measured on each subject.

The variables are
    group -- coded A and B
    alpha -- alphawave frequency