Question

Given two dependent random samples with the following results:

Population 1 45 46 27 36 38 33 15

Population 2 42 32 42 41 25 28 19

Use this data to find the 95% confidence interval for the true difference between the population means. Let d = (Population 1 entry -- (Population 2 entry). Assume that both populations are normally distributed.

Solution:

Step 1. Find the mean of the paired differences, d-bar . Round your answer to one decimal place. Answer: ____________________

Step 2. Find the critical value that should be used in constructing the confidence interval. Round your answer to three decimal places. Answer: ____________________

Step 3. Find the standard deviation of the paired differences to be used in constructing the confidence interval. Round your answer to one decimal place. Answer: ____________________

Step 4. Construct the 95% confidence interval. Round your answers to one decimal place. Answer: Lower endpoint: _______________ Upper endpoint: _______________

Answer 1