In: Statistics and Probability
To improve driver safety, Federal government is always encouraging states to lower the variance of stopping distances of automobiles on wet roads. LDOTD engineers claim that the variance of stopping distances of automobiles on wet roads in Louisiana is really smaller than the variance of stopping distances of automobiles on dry roads because of the materials used to build the roads. To test the claim for allocation of highway funds, Federal Department of Transportation tested 16 automobiles traveling at the same speed for stopping distances on wet roads and then on the dry roads in Louisiana. On the wet roads the standard deviation of the stopping distances was 32 feet while on dry roads it was 16 feet.
a) Test the claim at 5% level of significance.
b) What are the implications of your conclusions in terms of driving safety recommendations?