The following scenario applies to the remaining exercises. In given Exercise, we presented a two-way table of counts for a random sample of people who had ever been married, demonstrating the proportions who smoked and who had ever been divorced. The numbers are shown again in the following table.
|
Smoking and Divorce, GSS Surveys, 1991- 1993
|
|
|
Ever Divorced?
|
|
Smoke?
|
Yes
|
No
|
Total
|
|
Yes
|
238
|
247
|
485
|
|
No
|
374
|
810
|
1184
|
|
Total
|
612
|
1057
|
1669
|
Because this survey was based on a random sample in the United States in the early 1990s, the data should be representative of the adult population who had ever been married at that time. Answer these questions for a randomly selected member of that population.
Exercise
The following two-way table of counts summarizes whether respondents smoked or not and whether they had ever divorced or not for persons in the 1991-1993 General Social Surveys who had ever been married.
|
Smoking and Divorce, GSS Surveys, 1991- 1993
|
|
|
Ever Divorced?
|
|
Smoke?
|
Yes
|
No
|
Total
|
|
Yes
|
238
|
247
|
485
|
|
No
|
374
|
810
|
1184
|
|
Total
|
612
|
1057
|
1669
|
a. Among those who smoked, what percentage has ever been divorced? Is this value a row percentage or a column percentage?
b. Among those who have ever been divorced, what percentage smoked? Is this value a row percentage or a column percentage?
c. What percentage of the overall sample did not smoke and had not ever been divorced?
d. Determine a complete set of row percentages.
e. Briefly explain whether the percentages found in part (d) indicate that there is an observed relationship between smoking habits and whether persons ever married had ever divorced or not.
Suppose that two people were randomly selected from that population, without replacement. What is the probability that one of them smoked but the other one did not (in either order)?