Refer to Exercise 10.54. The authors also collected information about accidents concerning seat belt usage. The article compared fatality rates for occupants using seat belts properly with those for occupants not using seat belts. The data are given here.

a. Calculate the odds of being killed in a harmful- event car accident for vehicle occupants who were using seat belts and those who were not using seat belts. Interpret the two odds.
b. Calculate the odds ratio of being killed in a harmful- event car accident with and without seat belts being used properly. What does this ratio tell you about the importance of using seat belts?
c. Is there significant evidence of a difference between vehicles with and without proper seat belt usage relative to the proportions of persons killed in a harmful-event vehicle accident? Use a = .05.
d. Place a 95% confidence interval on the odds ratio. Interpret this interval.
In exercise

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Seat Belt Usage Seat Belt 16,001 7,758,634 7774,635 No Seat Belt Total Killed Survived Total 31,199 2,791 887 2,823,086 47200 10,550,521 10,597721 Air Bag Installed Yes No Total 27924 Killed Survived Total 47200 10.550.521 10,592721 19276 5,723539 5.742,815 4,826,982 4,854.906