Question

To illustrate the effects of driving under the influence (DUI) of alcohol, a police officer brought a DUI simulator to a local high school. Student reaction time in an emergency was measured with unimpaired vision and also while wearing a pair of special goggles to simulate the effects of alcohol on vision. For a random sample of nine teenagers, the time (in seconds) required to bring the vehicle to a stop from a speed of 60 miles per hour was recorded. Complete parts (a) and (b). Note: A normal probability plot and boxplot of the data indicate that the differences are approximately normally distributed with no outliers.

Subject: 1 2 3 4 5 6 7 8 9

Normal, Xi: 4.47 4.34 4.58 4.56 4.31 4.80 4.55 5.00 4.79

Impaired, Yi: 5.77 5.67 5.51 5.29 5.90 5.49 5.23 5.61 5.63

(a) Whether the student had unimpaired vision or wore goggles first was randomly selected. Why is this a good idea in designing the experiment?

a. This is a good idea in designing the experiment because reaction times are different

b. This is a good idea in designing the experiment because the sample size is not large enough

c. This is a good idea in designing the experiment because it controls for any "learning" that may occur in using the simulator

(b) Use a 95% confidence interval to test if there is a difference in braking time with impaired vision and normal vision where the differences are computed as "impaired minus normal."

The lower bound is:

The upper bound is:

State the appropriate conclusion.

a. There is insufficient evidence to conclude there is a difference in braking time with impaired vision and normal vision

b. There is sufficient evidence to conclude there is a difference in braking time with impaired vision and normal vision.

Answer 1

a)

c. This is a good idea in designing the experiment because it controls for any "learning" that may occur in using the simulator
b)

b. There is sufficient evidence to conclude there is a difference in braking time with impaired vision and normal vision