A highway safety institution conducts experiments in which cars are crashed into a fixed barrier at 40 mph. In the? institute's 40-mph offset? test, 40% of the total width of each vehicle strikes a barrier on the? driver's side. The? barrier's deformable face is made of aluminum? honeycomb, which makes the forces in the test similar to those involved in a frontal offset crash between two vehicles of the same? weight, each going just less than 40 mph. You are in the market to buy a family car and you want to know if the mean head injury resulting from this offset crash is the same for large family? cars, passenger? vans, and midsize utility vehicles? (SUVs). The data in the accompanying table were collected from the? institute's study. Complete parts? (a) through? (d) below.
Test the hypothesis that the mean head injury for each vehicle type is the same at the a=0.01 level of significance.
c. Use technology to find the? F-test statistic for this data set.
d. Use technology to find the P-value.
Large Family Cars / Passenger Vans / Midsize Utility Vehicles
261 149 227
135 236 214
409 343 184
529 698 306
148 545 349
626 472 549
167 320 400