Public Opinion • Public Opinion is the aggregation of people’ view

about issues, situations, and public figures. • Why is Public Opinion important? • Public opinion can shape public opinion by

providing policymakers with information. – Provides outlet for citizen voice in Representative

Democracy

• Should elected officials pay attention to polls?– Trustee vs Delegate Models of Representation

Trends in Opinion

The Economy and the 2008 Election

Presidential Approval RatingsHealthcare Reform Attitudes in NMWhat is your opinion regarding the current state of health care in New Mexico

Fine as is

Minor Changes

(24%)

Major Changes(45%)

Completely Rebuilt(27%)

Measuring Public Opinion- Sampling• Public opinion polls are the primary tool used to assess

how the public feels about particular issues, and is a critical tool for elected officials.

• Because you cannot ask the entire public questions about any particular issue, pollsters must rely on samples. – Target Population : Group of people inferences will

be drawn from.– Sample Population : Part of the target population

selected for analysis.• Public opinion is unfortunately often inconsistent at the

individual level, which raises questions about the validity of attitudes.

• However, at the aggregate level attitudes seem to be rather stable.

The Scientific Approach to Polling• There is a scientific method used to ensure that

a survey is not biased.

• When samples mirror the population they are said to be “Representative”.

• Randomness is critical to sampling.– Randomness implies that each person within the

entire population being polled has an equal chance of being chosen.

Inferences about the Population• Values calculated from samples are used to make

conclusions (inferences) about unknown values in the population

• Variability– different samples from the same population may yield

different results for a particular value of interest

– estimates from random samples will be closer to the true values in the population.

– how close the estimates will likely be to the true values can be calculated -- this is called the margin of error (usually +/- 3%) : The larger the sample size the smaller the sampling error (probability and rule of large numbers).

Sources of Selection Bias• Selection Bias is bad because it systematically

favors certain outcomes based on who is asked to participate.

• Voluntary response sampling– allowing individuals to choose to be in the sample– Classic example is setting up a table in SUB

• Convenience sampling– selecting individuals that are easiest to reach– often used for tough to reach groups (Dreamers,

Homeless)

– Both of these techniques are biased– systematically favor certain outcomes

Simple Random Sampling• Each individual in the population has the same

chance of being chosen for the sample

• Each group of individuals (in the population) of the required size (n) has the same chance of being the sample actually selected

• Random selection:– “drawing names out of a hat”– table of random digits– computer software - CATTI System

Probability Sample

• A sample chosen by chance

• Must know what samples are possible and what chance, or probability, each possible sample has of being selected

• A SRS gives each member of the population an equal chance to be selected

Cautions about Sample Surveys• The following are all examples of measurement error, or the

error that arises from attempting to measure something as subjective as opinion

• Undercoverage– some individuals or groups in the population are left out of the

process of choosing the sample• Nonresponse

– individuals chosen for the sample cannot be contacted or refuse to cooperate/respond

• Response bias– behavior of respondent or interviewer may lead to inaccurate

answers or measurements• Wording of questions

– confusing or leading (biased) questions; words with different meanings

Undercoverage and Non-Response Bias

• Doing internet surveys have become very popular due to costs and easy implementation.– How might this approach lead to

undercoverage?

• High non-response rates among particular populations can also be a problem.

Asking the UninformedWashington Post National Weekly Edition (April 10-16, 1995, p. 36)

• A 1978 poll done in Cincinnati asked people whether they “favored or opposed repealing the 1975 Public Affairs Act.”– There was no such act!– About one third of those asked expressed

an opinion about it.

Response Bias

Interviewer Effect• Can you think of any ways in which

people may be influenced by the people actually conducting the interview?

• Some examples include:– Race and Gender of interviewer– Facial Expressions to answers given

Response Bias

Wording of Questions• Questions should be simple and non-biased in

nature. They should not have different meanings.

• Here is an example of a biased question:– If you found a wallet with $20 in it, would you do

the right thing and return the money?– If you found a wallet with $20 in it, would you return

the money?

• You must also be cautious of “loaded” terms such as welfare or illegal immigrant.

Order of Questions• How often do you normally go out on a

date? About _ times a month?

• Why is asking the following question right after this one a problem?

• How happy are you with life in general?

Polling Issues Facing 2008 Election

• The “Bradley Effect”– Potential over-estimation of Obama vote

due to social desirability.

• The inability of most polls to capture first time voters, particularly the youth vote.

• What do you think, can we trust the polls?

• What are our alternatives?

The Socialization Process

• Political socialization is the process of acquiring political attitudes that begins at childhood.

• Family has been most critical soc. agent– Children usually have the same party preference as

their parents, especially when both parents have the same party identification.

• Has changes in family structure decreased impact of family in socialization process?

• What is the role of Education in Socialization?– Learn the “rules of the game” in politics– Exposed to different people and views– Increases general awareness and knowledge of

political issues

Are Schools Socializing Anymore?

• Many argue that schools are not doing a good job of providing basic political concepts to students.

• Perception vs. Reality (Studies of HS Students)– More than 50% did not know # of US senators– Over 60% could not name three branches of

government– One third did not know that the first ten

amendments are the bill of rights.• Recent studies suggest things might even get

worse in college!• What are your thoughts?

• What is the Media’s role in Public Opinion?• Most Americans get their political

information from TV, leading many to call the Media the 4th branch of government.

• Recent surveys of high school students indicate that television is more important in political socialization than family or school.

• Others contend that media is not as powerful as we think because everyone has pre-conceived opinions.

• How significant is the media in socialization?

• Socioeconomic Status Differences– How does income influence public

opinion?

• The wealthy are more likely to be conservative, and less likely to support government aid programs. However, education tends to lead to more liberal views on policies.

• There are also significant differences in public opinion by Race, Gender, and Religious affiliation.