In the General Social Survey, an ongoing nationwide survey done by the National Opinion Research Center at the University of Chicago, a question asked is whether a respondent favors or opposes capital punishment (the death penalty) for persons convicted of murder. The output for this exercise compares the proportions who said that they were opposed to the death penalty in the year 2008 and the year 1993 (Data sources: GSS-08 and GSS-93 datasets on the companion website).
a. What proportion of the year 2008 sample was opposed to the death penalty? What proportion of the year 1993 sample was opposed?
b. What is the estimated difference between the proportions opposed to the death penalty in the 2 years?
c. Write the 95% confidence interval given in the output. Then interpret this interval in the context of this situation.
d. Provide the formula used to calculate the interval, and substitute appropriate numerical values into the formula.