For Exercises 51–54, use the Crash data set, which contains information about the severity of injuries sustained by crash dummies when the National Transportation Safety Board crashed automobiles into a wall at 35 miles per hour.
Question 12.53
crash
53. Chest Injury and protection Device. The variable chest_in is a measure of the severity of the chest injury suffered by the crash dummy. The variable protect2 categorizes the type of protection that the vehicle offers: 1 = manual seat belts, 2 = motorized seat belts, 3 = passive seat belts, 4 = dual air bags. Would you expect the population mean severity of chest injuries suffered by the dummies to be the same for all categories of protection? Use technology to perform the analysis of variance, using . Comment on the results.
12.1.53
.: Not all the population means are equal. Reject if the . . Since the is not , we do not reject . There is insufficient evidence that not all the population means are equal.
