Table 7.17 comes from a General Social Survey. Subjects were asked whether methods of birth control should be available to teenagers and how often they attend religious services.

a. Fit the independence model. Describe the lack of fit.

b. Using equally spaced scores, fit the linear-by-linear association model. Describe the association. Test goodness of fit. Test independence by using the ordinality, and interpret.

c. Fit the L × L model using column scores {1, 2, 4, 5}. Explain why a fitted local log odds ratio using columns 2 and 3 is double a fitted local log odds ratio using columns 1 and 2 or columns 3 and 4. What is the relation between the odds ratios?

Table 7.17 Data for Exercise 7.13 on religion and birth control.

Teenage Birth Control Religious Strongly Strongly Attendance Agree Agree Disagree Disagree Never 49 49 19 9 Less than once a year 31 27 11 11 Once or twice a year 46 55 25 8 Several times a year 34 37 19 7 About once a month 21 22 14 16 2–3 times a month 26 36 16 16 Nearly every week 8 16 15 11 Every week 32 65 57 61 Several times a week 4 17 16 20