There are five cities in a politician's district but redistricting has been proposed for the state. The politician would like to know which city he should try to remove from his district. He plans to conduct a survey to find out his approval rating. Which one of the following sampling plans would be most useful for his purposes?
a. Take a stratified sample with political parties as the strata.
b. Take a stratified sample with the five cities as the strata.
c. Take a simple random sample across his district.
d. Take a cluster sample with the five cities as clusters.
Question 2
A company that produces electronics (stereos, TV's, DVD players, etc.) is thinking about adding an incentive program to the contracts of its employees. To learn about the opinion of its employees regarding this idea, a survey will be sent out to a sample of the employees. To ensure that employees of all three plants are repre-sented in the survey, the statistician decides to take a sample of employees from each of the three plants. At each plant, a list is available of all employees. A 1-in-20 systematic sample will be taken from each plant. What sampling technique is being used to sample the employees?
a. simple random
b. cluster
c. stratified
d. multi-stage