In the Health ABC Study, 538 subjects owned a pet and 1975 subjects did not. Amo
ID: 3060026 • Letter: I
Question
In the Health ABC Study, 538 subjects owned a pet and 1975 subjects did not. Among the pet owners, there were 310 women; 986 of the non-pet owners were women. Find the proportion of pet owners who were women. Do the same for the non-pet owners. (Be sure to let Population 1 correspond to the group with the higher proportion so that the difference will be positive. Round your answers to three decimal places.) Give a 95% confidence interval for the difference in the two proportions. (Do not use rounded values. Round your final answers to three decimal places.)
Explanation / Answer
The statistical software output for this problem is:
Two sample proportion summary confidence interval:
p1 : proportion of successes for population 1
p2 : proportion of successes for population 2
p1 - p2 : Difference in proportions
95% confidence interval results:
Hence,
a) Proportion of women pet owners = 310/538 = 0.576
b) Proportion of women non pet owners = 986/1975 = 0.499
c) 95% confidence interval: (0.030, 0.124)
Difference Count1 Total1 Count2 Total2 Sample Diff. Std. Err. L. Limit U. Limit p1 - p2 310 538 986 1975 0.076967672 0.024092967 0.029746325 0.12418902