Outline 1. Definition 2. When and why to use surveys 3. How to create a survey Surveys

Surveys - Definition A survey is a procedure for systematically collecting information about attitudes, preferences, knowledge, or behavior by asking people questions. We distinguish between surveys and survey research, the purpose of which is to increase scientific knowledge (for example, by testing theories). Surveys

When to Use Surveys When you want information about a population, but you cannot measure the whole population. It is usually the case that you cannot measure whole population Doing so is unnecessary Population = all the cases of interest. Surveys

Survey research - Definition Survey research has 3 major characteristics: Asking people questions using a formal procedure Given those characteristics, survey research is different from other field methods. E.g., results of case studies may not be generalizable Surveys

Survey research - Definition Survey research has 3 major characteristics: Using a quantitative method that requires standardized information as input Surveys

Survey research - Definition Survey research has 3 major characteristics: Generalizing results from sample to population it was drawn from Information is obtained from a sample and must be generalizable to the population the sample was drawn from Surveys

When to Use Survey Research Two distinct forms of survey research: Exploratory Used in new research areas where little theory has developed “descriptive” Of course, the existence of a correlation is not proof of causation, but one can test a hypothesis about cause by looking for the correlation. Surveys

When to Use Survey Research Two distinct forms of survey research: Exploratory Explanatory Looking for evidence of cause-effect relations among variables “If C causes D, then C and D should be correlated.” Of course, the existence of a correlation is not proof of causation, but one can test a hypothesis about cause by looking for the correlation. Surveys

Advantages of survey approach Surveys are: Cheap Relative to measuring whole population Surveys

Advantages of survey approach Surveys are: Cheap Practical Can be done in a short time Can be done over phone or through mail or internet Surveys

Advantages of survey approach Surveys are: Cheap Practical Accurate Results true of population within a small margin of error Surveys

Margin of Error A range of values True population value is likely to be in this range. If range is large, survey results are not useful Size of range depends upon sample size and confidence level chosen for estimating population value. Here, confidence level refers to confidence in the process – we have confidence that true population value will be in that range of values on (1-)*100% of occasions that we use this procedure. Surveys

Margin of error = range of values which contains population value % Value obtained from sample

How to create a survey Research questions Design Survey questions Sampling procedure Administration procedure Analyzing the results Surveys

Research question Start with a behavioral theory. Use it to generate research questions. Specify type of information that will (or won’t) meet your scientific objectives Surveys

Research question Be as specific as possible Think about interpretation In reports, you won’t discuss the actual questions on your survey instrument – you’ll discuss some theoretical construct What is it? Surveys

Design Longitudinal Same samples measured at different times Potential problem with loss of subjects Can take a long time to get data with this design, but if the results differ, it can’t be because of cohort effects, since the same people are involved (except for attrition effects). But it’s difficult to specify whether differences reflect change in society or change in subjects. Surveys

Design Longitudinal Cross-sectional One or more samples measured at one time If groups differ, it’s difficult to say why E.g., compare 20 year olds to 50 year olds – do their results differ because of age? Or cohort effect? Surveys

Design Longitudinal Cross-sectional Successive independent samples Different samples at different times Samples supposed to be drawn from same population – but that may be arguable if interval is long This design can not measure change in individuals. It can measure change in the population if the same population is sampled each time. Surveys

Survey questions If a survey exists that does the job, use it Otherwise… Write a first draft Surveys

Survey questions If a survey exists that does the job, use it Otherwise… Write a first draft Get feedback and revise draft Surveys

Survey questions If a survey exists that does the job, use it Otherwise… Write a first draft Get feedback and revise draft Pretest your questionnaire Surveys

Survey questions If a survey exists that does the job, use it Otherwise… Write a first draft Get feedback and revise draft Pretest your questionnaire Edit questions Surveys

Survey questions If a survey exists that does the job, use it Otherwise… Write a first draft Get feedback and revise draft Pretest your questionnaire Edit questions Formalize procedures Surveys

Survey questions Avoid bias “Do you believe in killing unborn babies?” “Should women be forced to bear unwanted children?” Surveys

Question from an ABC poll “Schiavo suffered brain damage and has been on life support for 15 years. Doctors say she has no consciousness and her condition is irreversible. Her husband and her parents disagree about whether she would have wanted to be kept alive. Florida courts have sided with the husband and her feeding tube was removed on Friday. What's your opinion on this case - do you support or oppose the decision to remove Schiavo's feeding tube?” Did incorrect use of the term “life support” influence the result? Surveys

A Gallup Poll question the same week “As you may know, on Friday the feeding tube keeping Terri Schiavo alive was removed. Based on what you have heard or read about the case, do you think that the feeding tube should or should not have been removed?”  Surveys

Fox News poll 18 days earlier “Terri Schiavo has been in a so-called 'persistent vegetative state' since 1990. Terri's husband says his wife would rather die than be kept alive artificially and wants her feeding tube removed. Terri's parents believe she could still recover and want the feeding tube to remain.  If you were Terri's guardian, what would you do? Would you remove the feeding tube or would you keep the feeding tube inserted?” Surveys

Issues Is “requiring tube feeding” the same as “being on life-support”? What does the public understand from the term “life-support”? Does the term bias the result? 27% Republican, 32% Democrat, 41% other or don't know.    Surveys

Issues Were results influenced by fact poll conducted in one evening? Were results influenced by whether the person involved was referred to as “Schiavo” or “Terri”? National Council on Public Polls (NCPP) says: "Surveys conducted on one evening, or even over two days, have more sampling biases -- due to non-response and non-availability -- than surveys which are in the field for three, four or five days.“ (http://www.ncpp.org/instant.htm) Surveys

Survey questions Be careful about social desirability Think about question sequence Use filter questions Surveys

Survey questions Don’t write two questions as one What would “No” mean in answer to this question: Do you support the Administration’s decisions to increase class sizes and start classes earlier in the day? Surveys

Survey questions Do the people you’re surveying have the information required to answer your questions? Check to see before you ask your questions Surveys

Survey questions “Are you familiar with the Liberal Party’s platform for this election?” before “In your view, will the Liberal Party’s platform produce positive or negative effects on the economy?” Surveys

Survey questions Is the meaning of your question clear? If you refer to “young people” do you mean 9 year olds? 25 year olds? Surveys

Survey questions Is the meaning of your question clear? “Which newspaper do you read?” Does this mean everyday? Sometimes? What if the respondent reads more than one? Point is you have to think about these issues before you have a respondent in front of you or on the phone. Surveys

Survey questions Is the meaning of your question clear? Be clear about the time frame of the behavior you are asking about E.g., CFQ asks about frequency of mental slips over the last six months Surveys

Sampling procedure Major task: to select a representative sample Representative sample – shares distribution of relevant characteristics with population Biased sample – distribution of relevant characteristics is systematically different. E.g., attitude to reduction in # of UWO parking spaces? Sample students who drive to UWO, not general student population. Surveys

Sampling procedure Some technical terms you need to know Population Sampling frame Sample Element Surveys

Sampling frame Sample Population Element

Types of sampling procedure Non-probability sampling Elements vary in probability of being chosen Those probabilities are not known Accidental samples Purposive samples Surveys

Types of sampling procedure Non-probability sampling Probability sampling Researcher knows the probability of inclusion for each element in population. Simple random sampling Stratified random sampling Simple random sampling occurs when every element in the population has an equal probability of being selected into the sample. Surveys

Administration procedures Phone Cheap & fast But who is home? Verbal instructions and response alternatives may be hard to remember Surveys

Administration procedures Phone Face-to-face Expensive But maximal control Interviewer can see whether respondent understands question Respondent may work harder Surveys

Administration procedures Phone Face-to-face Mail Inexpensive Significant problem with response bias Surveys

Analyze the Results Select a data analysis procedure before you collect data. Correlations Path analysis Factor analysis Surveys