Related questions with answers

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.

\begin{matrix} \text{Subject} & \text{1} & \text{2} & \text{3} & \text{4} & \text{5} & \text{6} & \text{7} & \text{8} & \text{9}\\ \text{Normal, }{ X_i} & \text{4.47} & \text{4.24} & \text{4.58} & \text{4.65} & \text{4.31} & \text{4.80} & \text{4.55} & \text{5.00} & \text{4.79}\\ \text{Impaired, }{ Y_i} & \text{5.77} & \text{5.67} & \text{5.51} & \text{5.32} & \text{5.83} & \text{5.49} & \text{5.23} & \text{5.61} & \text{5.63}\\ \end{matrix}

(a) Whether the student had unimpaired vision or wore goggles first was randomly selected. Why is this a good idea in designing the experiment? (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. "Note: A normal probability plot and boxplot of	the data indicate that the differences are approximately normally distributed with no outliers.

Driving under the influence of alcohol (DUI) is a serious offense. The following data give the ages of a random sample of 50 drivers arrested while driving under the influence of alcohol. This distribution is based on the age distribution of DUI arrests given in the Statistical Abstract of the United States.