Chapter 7: Survey Research. Psychology 2301 Introduction to Research Methods University of Houston

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1 Chapter 7: Survey Research Psychology 2301 Introduction to Research Methods University of Houston

2 Survey Research Employs questionnaires and interviews to ask people about themselves Attitudes Beliefs Demographic information

3 Survey Research: Sampling Just like we have to go from the abstract level of constructs to the concrete level of operational definitions, a similar translation is required when choosing participants. The population is an abstract idea of who we want to study, but we never actually measure the population. Instead, we have to choose a sample of real people that are available (and willing!) for investigation.

4 Survey Research: Sampling A population is comprised of all individuals of interest A sample is comprised of individuals that represen the population Data is collected on samples, not populations Then, from the data we collect on the sample, we extrapolate results to population. In other words, we generalize our findings to the population. Remember external validity?

5 Sampling: Example Research Question: Does the University of Houston student body think Frontier Fiesta is a good event? Who is the population of interest?

6 Gathering a Sample Population Sample University of Houston Student Body Students

7 Extrapolate Results Sample Population Students University of Houston Student Body

8 Sample Size The larger the sample the more accurate the results. Why? Reduces sampling error. A larger sample will decrease the length of the confidence interval. However, the sample required is not a straight percentage of the population. (see Table 7.1, p. 130).

9 Question.... How large of a sample is necessary to forecast election results?

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11 Sampling Techniques Probability Sampling Each member of a population has a specifiable probability of being chosen Best way to draw inferences about a population Expensive and time consuming

12 Probability Sampling Simple random sample Stratified random sample Cluster sampling

13 Simple Random Sample Every member of the population has an equal probability of being selected for the sample

14 Simple Random Sample: Example Research Question: Does the University of Houston student body think about Frontier Fiesta is a good event? Obtain a list of every student that attends the University of Houston Choose students from the list randomly

15 Stratified Random Sampling However, suppose that you are interested in comparisons between a majority group and several minority groups. You are concerned that simple random sampling may result in too few representatives of these minority groups to make comparisons. In this case, you could randomly select participants within their groups, such that the final percentage of participants from each group reflects their percentage in the population.

16 Nonprobability Sampling The probability of selection is not known Little effort is made to ensure that the sample accurately reflects the population Most psychological research conducted in this manner Inexpensive and convenient

17 Nonprobability Sampling Haphazard sampling Quota sampling

18 Haphazard Sampling Also known as convenience sampling Increases sampling error because sample may not be representative of the population it represents Why is this problematic?

19 Quota Sampling Quota sampling is the nonprobability version of stratified random sampling. The population is broken down into groups, which are then sampled separately. However, sampling is haphazard, not random.

20 Evaluating Samples: Response Rate The percentage of the people in the sample who completed the survey Low response rates may may compromise generalizability Why?

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22 Surveys: Question Wording Simplicity Double-barreled questions Loaded questions Negative wording Yea/Nay saying

23 Simplicity The purpose of the survey is to gather data in a quick and efficient manner The purpose of the survey is NOT to confuse the respondent If questions are confusing, you might be measuring something different (lack of construct validity) However, beware of over-simplicity! Remember the problem with high face validity?

24 Double-Barreled Questions Do not use them Questions that ask the respondent two things at once Example: Should tax dollars be spent to help construct Reliant field and the Metro rail?

25 Negative wording Again, to avoid confusing the participant, you should avoid negative wording (when possible). Thus, Do you not like green eggs and ham? should be phrased Do you dislike green eggs and ham?

26 Yea- and Nay-saying If your questions are consistently worded so that agreement with an idea is always represented by one response (e.g., yes ) then participants could be lulled into responding automatically instead of thoughtfully. Of course, you can t just add a not to the sentence. Re-write it using different words: UH parking sucks big time becomes UH parking fills me with joy

27 Loaded Questions Avoid them Questions that are written to lead a respondent to answer a certain way Often include negative connotations

28 Loaded Questions: Example Anti-Choice: Do you favor killing innocent children through abortion? Pro-Abortion: Do you favor a woman s inalienable right to have an abortion? These two questions might elicit different responses

29 Surveys: Responses Closed-Ended Questions Easier to score Limited response options (more structure) Decrease fidelity Need to be more familiar with construct Open-Ended Questions More expensive to score (time consuming)

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