American Government American Government and Organizationand Organization

PS1301PS1301

Friday, 24 OctoberFriday, 24 October

Measuring Public OpinionMeasuring Public Opinion

Non scientificNon scientific Straw pollsStraw polls

ScientificScientific Based on probability samplingBased on probability sampling

The Logic of Probability SamplingThe Logic of Probability Sampling

Difference between a population and a sampleDifference between a population and a sampleHomogeneity V. HeterogeneityHomogeneity V. Heterogeneity

If everyone were the same we would not need to sample.If everyone were the same we would not need to sample. One person could be surveyed to find out the characteristics One person could be surveyed to find out the characteristics

of the entire population.of the entire population.

Variation in what we study; precisely why we study itVariation in what we study; precisely why we study itFor a sample to be useful in providing information of For a sample to be useful in providing information of the population from which it is drawn must be the population from which it is drawn must be representativerepresentativeEssentially the sample must contain the same variation Essentially the sample must contain the same variation as in population as in population

Principle of Probability SamplingPrinciple of Probability Sampling

A sample will be representative of the population A sample will be representative of the population from which it is selected if all members of the from which it is selected if all members of the population have an population have an equal chanceequal chance of being selected of being selected in the sample. in the sample.

We can do this by selecting respondents We can do this by selecting respondents randomlyrandomly; ; each respondent has an equal chance of being each respondent has an equal chance of being selectedselected

Accuracy is a function of sample size (and Accuracy is a function of sample size (and proportion).proportion).

Accuracy is also a function of the way the question Accuracy is also a function of the way the question is worded (more on this later) as well as context is worded (more on this later) as well as context

Question wording: Question wording: Example of AbortionExample of Abortion

Hard reasonsHard reasons women’s health seriously threatenedwomen’s health seriously threatened raperape birth defectsbirth defects

Soft reasonsSoft reasons low incomelow income not married and does not want to marrynot married and does not want to marry married but does not want more childrenmarried but does not want more children interfered with work or educationinterfered with work or education

Question wording Question wording

““Should abortion be legal as it is now, or Should abortion be legal as it is now, or legal only in the cases of rape, incest, or to legal only in the cases of rape, incest, or to save the life of the mother, or should it not save the life of the mother, or should it not be permitted at all?”be permitted at all?” 48% legal as it is now48% legal as it is now 43% limited to rape, incest, health of mother43% limited to rape, incest, health of mother 9% not permitted at all9% not permitted at all

Source: CBS/NYT January 1989Source: CBS/NYT January 1989

Question wordingQuestion wording

““Do you think abortions should be legal Do you think abortions should be legal under any circumstances, legal under under any circumstances, legal under certain circumstances, or illegal under all certain circumstances, or illegal under all circumstances?circumstances? 28% legal28% legal 53% under certain circumstances53% under certain circumstances 19% illegal19% illegal

Source: Gallup/Newsweek January 1989Source: Gallup/Newsweek January 1989

DifferencesDifferences

Same time, same sample. Why the Same time, same sample. Why the difference? difference?

Respondents were not given the same Respondents were not given the same alternatives. Explicitly state circumstances alternatives. Explicitly state circumstances that fit the “hard reasons”.that fit the “hard reasons”.

Other ExamplesOther Examples

If a woman wants to have an abortion and her doctor If a woman wants to have an abortion and her doctor agrees to it, should she be allowed to have an abortion agrees to it, should she be allowed to have an abortion or not? Yes 65%or not? Yes 65%Please tell me whether or not it should be possible for a Please tell me whether or not it should be possible for a pregnant woman to obtain a legal abortion if she wants it pregnant woman to obtain a legal abortion if she wants it for any reason? Yes 36%for any reason? Yes 36%Do you agree or disagree with the following statement: Do you agree or disagree with the following statement: Every woman who wants to have an abortion should be Every woman who wants to have an abortion should be able to have one? Agree 61%able to have one? Agree 61%Please tell me whether or not it should be possible for a Please tell me whether or not it should be possible for a pregnant woman to obtain a legal abortion if she wants it pregnant woman to obtain a legal abortion if she wants it for any reason. Yes 41%for any reason. Yes 41%

Views on Abortion by ReligionViews on Abortion by Religion

IdeologyIdeology

A package of ideas, a way of A package of ideas, a way of organizingorganizing one’s thinking about political issues and one’s thinking about political issues and leaders. Anchored by core values that leaders. Anchored by core values that serve to structure other ideasserve to structure other ideas

Liberal vs. conservativeLiberal vs. conservative

A core value that distinguishes them and A core value that distinguishes them and influences their positions on a variety of influences their positions on a variety of issues is whether government should issues is whether government should actively promoteactively promote individual equality individual equality. .

Liberals favor active government Liberals favor active government intervention to ensure equality intervention to ensure equality flat rate vs. regressive rateflat rate vs. regressive rate income tax vs. sales taxincome tax vs. sales tax

Right vs. LeftRight vs. Left

Direction comes from French political Direction comes from French political tradition tradition

Those who generally supported the Those who generally supported the policies of the monarch were seated to his policies of the monarch were seated to his right and those who proposed changes in right and those who proposed changes in the system were arranged to his left.the system were arranged to his left.

At the extremes individuals are extremely At the extremes individuals are extremely dissatisfied and want revolutionary changedissatisfied and want revolutionary change

Distribution over timeDistribution over time

Who are the Liberals?Who are the Liberals?

PoorPoor

Low EducationLow Education

Low Strata OccupationLow Strata Occupation

MinorityMinority

UrbanUrban

Jew, CatholicJew, Catholic

DemocratsDemocrats

Who are the Conservatives?Who are the Conservatives?

WealthyWealthy

High EducationHigh Education

High Status OccupationHigh Status Occupation

WhiteWhite

SuburbanSuburban

ProtestantProtestant

RepublicanRepublican

QuizQuiz

What is the difference between liberals What is the difference between liberals and conservatives?and conservatives?