To compare the commuting times in various locations, independent and random samples were obtained in each of six different U.S. cities, as displayed in Section
12. .1’s The Morning Rush. Using the commute time data located in Exercise
12. .2 on page 586:
a. Construct a box plot showing the six cities side by side.
b. Does your graph show visual evidence suggesting that the city has an effect on the average morning commute time? Justify your answer.
c. Using the ANOVA technique, do these data show sufficient evidence to claim that the city has an effect on the average morning commute time? Use a = 0.05
d. Does the statistical answer found in part c agree with your graphical display in part a and your response in part b? Explain why your answers agree or disagree, citing statistical information learned in this chapter.
e. “Does the sample show that the city has an effect on the amount of time spent commuting to work?” “Does the sample show that the city has an effect on the average amount of time spent commuting to work?” Are these different questions? Explain.