In a bumper test, three types of sub-compact cars
were deliberately crashed into a barrier at 5 mph with the resulting damage (in dollars) recorded.
Eight test cars of each type were crashed. Test results indicated that post-hoc procedures were
warranted. The TUKEY HSD approach was used with the following results:

Using an overall significance level of 5%, is there evidence that one type of car had less bumper
damage than the others? Which car appears to have the least bumper damage?
A) Yes, the confidence interval results show that Car 1 has less damage than 2 or 3.
B) Yes, the confidence interval results show that Car 2 has less damage than 1 or 3.
C) Yes, the confidence interval results show that Car 3 has less damage than 1 or 2.
D) No, there is not enough evidence to say that one type of car has less damage than the others because the intervals all overlap.

Question

In a bumper test, three types of sub-compact cars
were deliberately crashed into a barrier at 5 mph with the resulting damage (in dollars) recorded.
Eight test cars of each type were crashed. Test results indicated that post-hoc procedures were
warranted. The TUKEY HSD approach was used with the following results:

Using an overall significance level of 5%, is there evidence that one type of car had less bumper
damage than the others? Which car appears to have the least bumper damage?
A) Yes, the confidence interval results show that Car 1 has less damage than 2 or 3. 
B) Yes, the confidence interval results show that Car 2 has less damage than 1 or 3. 
C) Yes, the confidence interval results show that Car 3 has less damage than 1 or 2. 
D) No, there is not enough evidence to say that one type of car has less damage than the others because the intervals all overlap.

Quizplus · Accepted Answer

The Answer of In a bumper test, three types of sub-compact cars
were deliberately crashed into a barrier at 5 mph with the resulting damage (in dollars) recorded.
Eight test cars of each type were crashed. Test results indicated that post-hoc procedures were
warranted. The TUKEY HSD approach was used with the following results:

Using an overall significance level of 5%, is there evidence that one type of car had less bumper
damage than the others? Which car appears to have the least bumper damage?
A) Yes, the confidence interval results show that Car 1 has less damage than 2 or 3. 
B) Yes, the confidence interval results show that Car 2 has less damage than 1 or 3. 
C) Yes, the confidence interval results show that Car 3 has less damage than 1 or 2. 
D) No, there is not enough evidence to say that one type of car has less damage than the others because the intervals all overlap.

In a Bumper Test, Three Types of Sub-Compact Cars