Refer to the previous exercise. A subject was called a monthly smoker if he or she had smoked cigarettes over an extended period of time. The 74 female monthly smokers had a mean HONC score of 5.4 (s = 3.5), and the 71 male monthly smokers had a mean HONC score of 3.9 (s = 3.6). Using software (such as MINITAB) that can conduct analyses using summary statistics, repeat parts b and c of the previous exercise.
In Previous Exercise.
b. Find the test statistic and P-value for H0: μ1 = μ2 against Ha: μ1 ≠ μ2. Interpret, and explain what (if any) effect gender has on the mean HONC score.
c. Do you think that the HONC scores were approximately normal for each gender? Why or why not? How does this affect the validity of the analysis in part b?