In Exercises, find the coefficient of variation for each of the two samples; then compare the variation. (The same data were used in Section 3-2.)

Speeding and Race Listed below are speeds (in mi/h) of cars on the New Jersey Turnpike by race of the driver. All cars are going in the same direction, and all of the cars are from New Jersey. The data are from Statlib and the authors are Joseph Kadane and John Lamberth.

Solution 21BSC

For White drivers:

We know that the mean of a given set of observations obtained by adding those observations and divide that result with number of given observations. The mean speed (in mi/h) of cars on the New Jersey Turnpike is

Therefore, the mean speed of cars on the New Jersey Turnpike for white drivers is

73 mi/h.

Step 2 of 6</p>

From the given information,

We know that variance of given set of sample value found as follows:

Therefore, the standard deviation of the given sample is.

Step 3 of 6</p>

We know that coefficient of variation for a sample found by

Therefore, the coefficient of variation for White drivers is 3.9%.