Analgesics. A pharmaceutical company tested three formulations of a pain relief medicine for migraine headache sufferers. For the experiment, 27 volunteers were selected and 9 were randomly assigned to one of three drug formulations. The subjects were instructed to take the drug during their next migraine headache episode and to report their pain on a scale of no pain to extreme pain 30 minutes after taking the drug.
a) State the null and alternative hypotheses, being careful to talk about Drug and Pain levels as well as parameters.
b) Perform an ANOVA on these data. What can you conclude?
c) Check the assumptions and conditions for an ANOVA. Do you have any concerns about the experimental design or the analysis?
d) Perform a multiple comparisons test to determine which drugs differ in terms of mean pain level reported.