The National Highway Transportation Safety Administration runs crash tests in which stock automobiles are crashed into a
Question:
The National Highway Transportation Safety Administration runs crash tests in which stock automobiles are crashed into a wall at 35 mph with dummies in both the passenger and the driver's seats. The THOR Alpha crash dummy is capable of recording 1 channel of data on the impact of the crash at various sites on the dummy. In this test 335 cars are crashed. The response variable is a measure of head injury. Researchers want to know if which seat the dummy is in affects head injury severity, as well as whether the type of car affects severity.
Here are partial box plots for the 2 different Seats (driver, passenger) and the 6 different Size classifications (compact, light, medium, mini, pickup, van):
A scatter plot of residuals vs. predicted values shows:
a) Are the conditions for two-way ANOVA met?
b) State the hypotheses about the main effects (both numerically and in words).
c) If so, perform the hypothesis tests and state your conclusion. Be sure to state it in terms of head injury severity, seats, and vehicle types.
Step by Step Answer:
Stats Data And Models
ISBN: 662
4th Edition
Authors: Richard D. De Veaux, Paul D. Velleman, David E. Bock