Polling and Public Opinion

1. Polling and Public Opinion Measuring Citizens’ Opinions, Attitudes and Beliefs

2. Polling and Measuring Public Opinion • How do we measure public opinion? • What is the difference between scientific polls and unscientific polls? • When and how can you trust polls? • What should the role of polls be in a democracy?

3. Elements of a Poll • Population—the people whose opinion you want to draw conclusions about. • Sample—the people you contact and who respond to the poll.

4. Brief History of Polling • Local opinion leaders • Straw Polls • Literary Digest Magazine • George Gallup and Scientific Polling

5. Scientific Polling • One of the simplest ways to draw an unbiased sample as close to the population of inference as possible is to use a simple random sample (SRS). • Simple Random Sample: a technique where each member of the population has an equal probability of becoming part of the sample. • Straw Polls are not SRS because each person is not equally as likely to be surveyed.

6. Elements of a Poll • Sample Size and Accuracy • Margin of Error (+/-) • Larger samples reduce the margin of error because there is less chance of a few unrepresentative responses altering the overall results. • Larger samples are more expensive

7. Elements of a Poll • Survey instrument • Questions asked the respondents • Professional pollsters try to ask questions that will not lead or confuse respondents

8. When and how far can you trust polls? • Source • Push Polls • Blurry Snapshots • Non-attitudes

9. Some thoughts • Public opinion as the basis for democracy • Not sure what it means… • Informed people know how far to trust it • Scientific polling and trusted sources • For better or worse... it's inextricably part of democracy