Refer to the auto accident injury data shown in Table 7.5.

a. Explain why the fitted odds ratios in Table 7.7 for model (GL, GS, LS, GI, LI, SI) suggest that the most likely case for injury is accidents for females not wearing seat belts in rural locations.

b. Consider the following two-stage model. The first stage is a logistic model with S as the response, for the three-way G × L × S table. The second stage is a logistic model with these three variables as predictors for I in the four-way table. Explain why this composite model is sensible, fit the models, and interpret results.