NonExperimental designs Surveys Psych 231 Research Methods in

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

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

n Sometimes you just can’t perform a fully controlled experiment n n Because of

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

n What are they? n n Questionnaires and interviews that ask people to provide

n What are they? n n Questionnaires and interviews that ask people to provide information about themselves Why conduct them? n Best way to collect some kinds of information: • Descriptive, behavioral, and preferential • e. g. , demographic information, recreational behavior, and attitudes n 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

n Advantages n n n One can investigate internal events (for example, attitudes &

n Advantages n n n 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

n Disadvantages n Correlational: causal claims shouldn’t be made • Note: surveys are sometimes

n Disadvantages n 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 n Non-response bias • Why doesn’t everybody respond? • Does response rate interact with variables of interest? n n 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

n Stage 1) Identify the focus of the study and select your research method

n Stage 1) Identify the focus of the study and select your research method n n n 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

n n Stage 2) Determining the research schedule and budget Stage 3) Establishing an

n n Stage 2) Determining the research schedule and budget Stage 3) Establishing an information base n Find out what’s been done, what’s known • E. g. , Find other related surveys n Stage 4) Identify the sampling frame n 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.

n Stage 5) Determining the sample method and sampling size n Review Probability and

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

A kind of convenience sampling methods commonly used Should leftover Halloween candy be given

A kind of convenience sampling methods commonly used Should leftover Halloween candy be given out to students who get an A on the exam? n Call 123 -4 YES if you think YES Call 123 -NONO if you think NO • 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

n Sampling error - how is the sample different from the population? n Confidence

n Sampling error - how is the sample different from the population? n 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

n Sampling error - how is the sample different from the population? n Response

n Sampling error - how is the sample different from the population? n 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

n Stage 6) Designing the survey instrument n Question construction: How the questions are

n Stage 6) Designing the survey instrument n 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.

Poor Was the FDC negligent by ignoring the warnings about Vioxx during testing and

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

Poor Should senior citizens be given more money for recreation centers and food assistance

Poor Should senior citizens be given more money for recreation centers and food assistance programs? a) Yes b) No Problem: asks c) Unsure two different questions Good Should senior citizens be given more money for recreation centers? a) b) c) Yes No Unsure Should senior citizens be given more money for food assistance programs? a) b) c) Yes No Unsure Good and poor questions

Poor Are you against same sex marriage and in favor of a constitutional amendment

Poor Are you against same sex marriage and in favor of a constitutional amendment to ban it? Good What is your view on same sex marriage? a) a) b) c) Yes No Unsure Problem: Biased in more than one direction b) c) 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: Asks two questions Good and poor questions

n Question types n Open-ended (fill in the blank, short answer) • Can get

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

Closed-ended What is the best thing about ISU? (choose one) n 1. Location n

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

if closed-ended n decide number/label of response alternatives • should use odd number (5

if closed-ended n decide number/label of response alternatives • should use odd number (5 or 7 best) • labels should be clear n decide scale • rating: PSY 231 is an important course in the major. 1 Strongly Agree Survey Questions 2 3 4 5 Agree Neutral Disagree Strongly Disagree

if closed-ended n decide scale • semantic differential: PSY 231 Important _____: _____: Unimportant

if closed-ended n 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

n Stage 7) Pre-testing the survey instrument n n Stage 8) Selecting and training

n Stage 7) Pre-testing the survey instrument n n Stage 8) Selecting and training interviewers n n n Fix what doesn’t seem to be working 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.