4.4 Let us suppose that a 2 x 2 factorial with variable coded to ± 1 is used to fit a logistic regression model in a drug study in which 20 subjects were allocated to each of the 4 treatment combinations. If the response is successful, then y = 1, and if the response is unsuccessful, then y = 0. The coefficients in the model are b0 = 1.4, b\ = 4.2, and b2 = 7.1. No interaction was found. Do the following:

(a) Compute the odds ratio for each coefficient and draw practical interpretations.

(b) Compute the asymptotic 95% confidence intervals for each odds ratio.