1. Non-Experimental designs: Surveys
Psych 231: Research Methods in Psychology

2. Non-Experimental designs
Sometimes you just can’t perform a fully controlled experiment
Because of the issue of interest
Limited resources (not enough subjects, observations are too costly, etc).
Surveys
Correlational studies
Quasi-Experiments
Developmental designs
Small-N designs
This does NOT imply that they are bad designs
Just remember the advantages and disadvantages of each
Non-Experimental designs

3. Surveys What are they? Why conduct them?
Questionnaires and interviews that ask people to provide information about themselves
Why conduct them?
Best way to collect some kinds of information:
Descriptive, behavioral, and preferential
e.g., demographic information, recreational behavior, and attitudes
To compliment experimental work
Good/common first step, can collect a lot of data about a lot of variables
Do not have to directly observe behaviors
Surveys

4. Advantages
One can investigate internal events (for example, attitudes & opinions)
Can generalize about an entire population based on relatively small samples of individuals
Large amounts of data can be collected quickly with relatively little cost (effort, time, etc.)
But they’re often not as “cheap” as you may think
Surveys

5. Surveys Disadvantages Correlational: causal claims shouldn’t be made
Note: surveys are sometimes used as part of an experimental design, which may allow testing of causal claims
Non-response bias
Why doesn’t everybody respond?
Does response rate interact with variables of interest?
Large data sets are sometimes difficult to analyze
Self-reports may not be truthful
Response set - tendency to respond from a particular perspective
Social desirability bias (e.g., how a “moral” person would answer)
Surveys

6. Stages of survey research
Stage 1) Identify the focus of the study and select your research method
What are the objectives of the research?
Is a survey method the best approach?
What kind of survey should be used?
Group administration
Mail surveys
Internet surveys
Telephone surveys
Face-to-face interviews
Focus group interviews
Stages of survey research

7. Stages of survey research cont.
Stage 2) Determining the research schedule and budget
Stage 3) Establishing an information base
Find out what’s been done, what’s known
E.g., Find other related surveys
Stage 4) Identify the sampling frame
The actual population that the sample is drawn from (as opposed to the ideal population)
Think of it as operationalizing the conceptual level population
Be aware of potential coverage error – when the sampling doesn’t lead to a good representativeness
Stages of survey research cont.

8. Stages of survey research cont.
Stage 5) Determining the sample method and sampling size
Review Probability and Non-Probability methods
Voluntary response method
Importance of sample size
Stages of survey research cont.

9. Voluntary response methods
A kind of convenience sampling methods commonly used
Should leftover Halloween candy be given out
to students who get an A on the exam?
Call 123-NONO if you think NO
Call 123-4YES if you think YES
Problem: Typically only individuals with strong opinions respond, so the results are often extremely biased
Daily show clip
Another fun poll result
Voluntary response methods

10. Importance of sample size
Sampling error - how is the sample different from the population?
Confidence intervals
An estimate of the mean or percentage of the population, based on the sample data
“John Doe has 55% of the vote, with a margin of error ± 3%”
Margin of error (that “± 3%” part)
The larger your sample size, the smaller your margin of error will be.
Which would you be more likely to believe
“We asked 10 people …”
“We asked 1000 people …”
Importance of sample size

11. Importance of sample size
Sampling error - how is the sample different from the population?
Response rate
What proportion of the sample actually responded to the survey?
Hidden costs here - what can you do to increase response rates
Non-response error (bias)
Is there something special about the data that you’re missing (From the people who didn’t respond)?
Importance of sample size

12. Stages of survey research cont.
Stage 6) Designing the survey instrument
Question construction: How the questions are written is very important
Clearly identify the research objectives
Do your questions really target those research objectives (think Internal and External Validity)?
Take care wording of the questions
Keep it simple, don’t ask two things at once, avoid loaded or biased questions, etc.
How should questions be answered (question type)?
Stages of survey research cont.

13. Good and poor questions
Was the FDC negligent by ignoring the
warnings about Vioxx during testing
and approving it for sale?
Yes No
Unsure
Do you favor eliminating the wasteful
excess in the public school budget?
If the FDC knew that Vioxx caused serious side effects during testing,
what should it have done?
Ban it from ever being sold
Require more testing before approving it
Unsure
Do you favor reducing the public school budget?
Yes No
Problem: emotionally
charged words
Good and poor questions

14. Good and poor questions
Should senior citizens be given more
money for recreation centers and
food assistance programs?
Yes No
Unsure
Should senior citizens be given more money for recreation centers?
Yes No
Unsure
Should senior citizens be given more money for food assistance programs?
Problem: asks two
different questions
Good and poor questions

15. Good and poor questions
Are you against same sex marriage
and in favor of a constitutional
amendment to ban it?
Yes No
Unsure
What is your view on same sex marriage?
I think marriage is a matter of personal choice
I’m against it but don’t want a constitutional amendment
I want a constitutional amendment banning it
Problem: Biased in
more than one direction
Problem: Asks two
questions
Good and poor questions

16. Survey Questions Question types
Open-ended (fill in the blank, short answer)
Can get a lot of information, but
Coding is time intensive and potentially ambiguous
Close-ended (pick best answer, pick all that apply)
Easier to code
Response alternatives are the same for everyone
Rating scales
Used for “how much” judgments
e.g., measures attitudes, agree/disagree
Take care with your labels
Range of scores, anchors
Survey Questions

17. Survey Questions Closed-ended Open-ended
What is the best thing about ISU? (choose one)
1. Location
2. Academics
3. Dorm food
4. People who sell things between Milner and the Bone
What is the best thing about ISU?
Survey Questions

18. Survey Questions if closed-ended
decide number/label of response alternatives
should use odd number (5 or 7 best)
labels should be clear
decide scale
rating: PSY 231 is an important course in the major.
Strongly Agree Neutral Disagree Strongly
Agree Disagree
Survey Questions

19. Survey Questions if closed-ended decide scale
semantic differential: PSY 231
Important _____: _____: _____: _____: _____: Unimportant
Boring _____: _____: _____: _____: _____: Interesting
nonverbal scale for children:
Point to the face that shows how you feel about the toy.
Survey Questions

20. Stages of survey research cont.
Stage 7) Pre-testing the survey instrument
Fix what doesn’t seem to be working
Stage 8) Selecting and training interviewers
For telephone and in-person surveys
Need to avoid interviewer bias
Stage 9) Implementing the survey
Stage 10) Coding and entering the data
Stage 11) Analyzing the data and preparing a final report
Stages of survey research cont.