The General Social Survey (GSS) has been collecting demographic, behavioral, and attitudinal information since 1972 to monitor changes within the US and to compare the US to other nations.1Support for capital punishment (the death penalty) in the US is shown in 1974 and in 2006 in the two-way table in Table 1.
Year: 1974, 2006
Favor: 937, 1945
Oppose: 473, 870
Total: 1410, 2815
Find a 99% confidence interval for the difference in the two proportions,P1 - P2 , where P1 and P2 represent the proportion supporting capital punishment in 2006 and 1974, respectively.
The 99% confidence interval is ? to ?
Is it plausible that the proportion supporting capital punishment has not changed?