The results of a recent poll on the preference of shoppers regarding two products are shown below.
Shoppers Favoring
|
Product
|
Shoppers Surveyed
|
This Product
|
|
A
|
800
|
560
|
|
B
|
900
|
612
|
- The point estimate for the difference between the two population proportions is:
- The standard error of pbar1 - pbar2 is (to 4 decimal places)
- The 95% confidence interval estimate for the difference between the populations favoring the product is to (to 3 decimal places)