The Gallup Poll correctly predicted George H. W. Bush's 1988 victory using only 4,089 interviews. Why, then, did the Gallup Poll in 1948 wrongly predict Dewey's victory over Truman when they used 50,000 interviews to make the prediction?
A)They only interviewed people in one state
B)They used multistage cluster sampling
C)They used quota sampling
D)They used random sampling

Question

Quizplus · Accepted Answer

In 1948, the Gallup Poll used quota sampling, which is prone to selection bias and can result in an unrepresentative sample. In contrast, in 1988, the poll used random sampling, which is more representative of the population and produces more accurate predictions.

The Gallup Poll Correctly Predicted George H