Discussion:
Hypothesis Testing on Multiple Population
Q: Dr. Michaella Evans, a statistics professor at the University of Maryland University College, drives from her home to the school every weekday. She has three options to drive there. She can take the Beltway, or she can take a main highway with some traffic lights, or she can take the back road, which has no traffic lights but is a longer distance. Being as data-oriented as she is, she is interested to know if there is a difference in the time it takes to drive each route.
As an experiment she randomly selected the route on 21 different days and wrote down the time it took her for the round trip, getting to work in the morning and back home in the evening. At the .01 significance level, can she conclude that there is a difference between the driving times using the different routes?
Time (in minutes) it took to get to work and back using:
|
Beltway
|
Main highway
|
Back road
|
|
88
|
79
|
86
|
|
94
|
86
|
78
|
|
91
|
75
|
79
|
|
88
|
83
|
96
|
|
98
|
74
|
97
|
|
84
|
72
|
73
|
|
90
|
|
68
|
|
77
|
|
|
You can check your critical value with the following table: https://www.statsoft.com/textbook/distribution-tables