8 In the 2012 presidential preelection surveys Pew Research

8. In the 2012 presidential pre-election surveys, Pew Research sampled 1,112 likely voters during October 4–7, 2012, and asked if they were planning to vote for Obama, and then asked the same question of a sample of 1,495 likely voters taken from October 24–28, 2012. However, in their last survey taken October 31–November 3, 2012, just before the election held on November 6, 2012, they asked this question of a sample of 2,709 likely voters. Why do you think Pew did this? (Select all that apply.)

A. The polling organization wants to increase the accuracy of its results.

B. The polling organization wants to increase the accuracy of its population.

C. Larger samples provide better information about the poll.

D. Larger samples provide better information about the sample.

E. Larger samples provide better information about the population.

23. An opinion poll calls 2000 randomly chosen residential telephone numbers, then asks to speak with an adult member of the household. The interviewer asks, \"How many movies have you watched in a movie theater in the past 12 months?\"

(b) In all, 1190 people respond. What is the rate (percent) of nonresponse? (Use 1 decimal place.)

25. Academic sample surveys, unlike commercial polls, often discuss nonresponse. A survey of drivers began by randomly sampling all listed residential telephone numbers in the United States. Of 44,628 calls to these numbers, 5355 were completed. What was the rate of nonresponse for this sample? (Only one call was made to each number. Nonresponse would be lower if more calls were made. Use 1 decimal place.)

Solution

8. A. The polling organization wants to increase the accuracy of its results.

E. Larger samples provide better information about the population.

23. The number of non-response = total - respond = 2000 - 1190 = 810

Rate of non-response = (810/2000)*100 = 40.5%

25. Number of non-responded calls = Total calls - completed calls = 44628 - 5355 = 39273

Rate of non-responded calls = (39273/44628)*100 = 88.0%