1. Explain the difference between independent samples and dependent samples. Classify the following as independent or dependent samples:
a. Weights of identical twins
b. The effectiveness of two different brands of ibuprofen
c. Effect of a new training program on time taken to complete a task, measured by a "before" and "after" test
d. Test scores of a group of students on a math test and a biology test.
2. Complete the following:
a. Select a variable. Compare the mean of the variable for a sample of 30 for one group with the mean of the variable for a sample of 30 for a second group. Use a z test.
b. Select a variable. Compare the mean of the variable for a sample of 10 for one group with the mean of the variable for a sample of 10 for a second group. Use a t test.
c. Select a variable that will enable you to compare proportions of two groups. Use sample sizes of at least 30. Use the z test for proportions.