"Pfizer Bares Belated Celebrex Study" reported in 2004 that "Pfizer Inc. revealed it completed a study four years ago that links its painkiller Celebrex to a 'statistically significant' increase in heart problems."24
a. Describe the two categorical variables of interest in Pfizer's study, identifying each as being explanatory or response.
b. Can we assume that Pfizer obtained a P-value that was more than 0.05 or less than 0.05?
c. Each of the variables you described in part (a) would have just two possible values, so the chi-square test would be based on a 2-by-2 two-way table. Was the chi-square statistic greater than 3.84 or less than 3.84?