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Survey Research. Survey data. Survey data are obtained when individuals respond to questions asked by interviewers or when the individual responds to questions that he has read Quantitative and qualitative information Census or sample? . Survey Sampling. Sample Survey
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Survey data • Survey data are obtained when individuals respond to questions asked by interviewers or when the individual responds to questions that he has read • Quantitative and qualitative information • Census or sample?
Survey Sampling • Sample Survey • Sample of the population (e.g., sample of Alberta CEOs) • Census Survey • Complete population (e.g., all CEOs in Lethbridge)
Functions • Descriptive • Causal (limited function) • Exploratory (limited function)
Information Provided by Surveys • respondent’s knowledge of facts • how many times a month do you buy cookies? • respondent’s attitudes • “chocolate chip is my favorite variety of cookie.” • May describe processes undertaken by respondent • Stages in the purchase decision, for example • usually self-report data
The type of information gathered depends on a survey’s objectives. • Surveys typically have multiple objectives
Classifications • Method of Communication • Telephone • Mail • Personal interview • Degree of Structure • Unstructured • structured • Degree of Disguise Limitations: Structure and disguise are not clear categories; most surveys are hybrids
Temporal classifications • Cross sectional studies • Longitudinal studies • Trend Studies • Samples general population at each point; complete turnover in who is actually sampled • Cohort studies (tracking studies) • Samples from one group over time; e.g., sample of a graduating class • Panel studies • sample cohort, same specific respondents each sample
Method of Communication • Media • Personal Interviews • Telephone Interviews • Self administered Questionnaires
Media • Human interactive • Electronic interactive: researcher and respondent interact using digital technology • Non-interactive media
Personal interview • Direct communication between business and consumers in which interviewers ask respondents questions in face to face situations • Key advantages: • Opportunities for feedback • Probing for complex answers • Length of interview
Personal interview • Direct communication between business and consumers in which interviewers ask respondents questions in face to face situations
Key advantages: Personal interview • Opportunities for feedback • Probing for complex answers • Length of interview • Completion rates • Ability to use props • High participation/low refusal rate (especially if using call back)
Key disadvantages: • Anonymity of respondent • Interviewer bias • Interviewer cheating • cost
Types of personal interviews • Door to door interviews: • Low refusal rates • Provide a more representative sample • Provide a less representative sample (under-representation of certain groups)
Types of personal interviews • Mall intercept: • Lower cost • Provide a larger sample • Useful if targeting particular population • Increased use of visual aids • Higher refusal rate • Provide a less representative sample
Telephone interviews • Considered to be the primary method of survey research • Why: • representative samples • Technology • Perception of anonymity
Key advantages: Telephone interview • Central location - increased quality of supervision • Computer assisted telephone interviewing - data entry • Speed • Cost
Anonymity- absence of face to face contact • Less interviewer cheating • Less researcher bias • Cooperation??? • Representative samples (RDD) • Call backs easier
Key disadvantages: • Cooperation • Lack of visual media • Limited duration
Mail and self-administered questionnaires • A very popular method of data collection
Types of Mail Surveys • Ad Hoc Mail Surveys: • Questionnaires for a particular project sent to selected names and addresses with no prior contact by the researcher. • Mail Panels: • Precontacted and screened participants who are periodically sent questionnaires. • A mail panel is a type of longitudinal study. A longitudinal study in one in which the same respondents are resampled over time.
Key advantages: Self-administered • Geographical flexibility • Cost • Respondent convenience - accuracy and reflection • Anonymity • Standardized questions - increase validity
Key disadvantages: Self-administered • Time • Length (6 pages) • Interviewers absence • Response rates
Tactics Employed to Increase Response Rate • Advance postcard or telephone call alerting respondent of survey • Follow-up postcard or phone call (coding/keying) • Monetary incentives (nickel, dime, quarter, half-dollar) • Premiums (pencil, pen, keychain, etc.) • Postage stamps rather than metered envelopes • Self-addressed, stamped return envelope • Assurances regarding length
• Promise of contributions to favorite charity • Entry into drawing for prize • Emotional appeals • Affiliation with universities or research institutions • Multiple mailings of the questionnaire • Bids for sympathy • Reminder that respondent participated in previous study • Interesting questions; well laid out • Ask the right people • A cover letter
Cover Letter • introduces who you are • purpose and importance of study • relevance of survey to respondent • especially if they receive several survey’s a week, need to be convinced survey results matter to them
why and how they were selected • why their input is crucial • e.g., “As a respected member of the Trustees, you have a unique perspective on....”) • big name sponsor, if any • e.g., University of Lethbridge, Heart Foundation, etc.
give due date • make reasonable but specific • contact number if they have any questions • include email these days too • end by thanking them for completing survey • explain direct incentive, if any (optional)
Not just the mail... • At point of service • Fax surveys (respond by fax; deliver by fax) • Email surveys • Computerized questionnaires (computer interactive) • Internet surveys
Factors Determining Choice of Particular Survey Method • Sampling Precision Required • Budget Available • The Need to Expose the Respondent to Various Stimuli • Quality of Data Required • Length of the Questionnaire
Necessity of Having Respondent Perform Certain Specialized Tasks • Incident Rate • Percentage of people or households in the general population that fit the qualifications to be sampled. • Degree of Structure of the Questionnaire
Types of Error in Survey Research • Random Sampling Error (Random error) • Error that results from chance variation • Impact can be decreased by increasing sample size and through statistical estimation (confidence interval) or “rule of thumb” • Systematic Error (non sampling error) • Error that results for the research design or execution.
Types of Systematic Error 1. Administrative Error • Error that results from improper execution. • Data Processing Error • Quality of data depends on quality of data entry. • Use of verification procedures can minimize
Sample Selection Error • Systematic error resulting from improper sampling techniques either in design or execution. • Interviewer Error • Data recorded incorrectly (error or selective perception). • Interviewer Cheating • Mitigate by random checks
2. Respondent Error • Humans interviewing humans... • Non-response error • Statistical difference between a survey that includes only those who responded and a survey that also includes those who failed to respond. • Non-respondent: person not contacted or who refuses to participate • Self selection bias: extreme positions represented
Response bias • Errors that result from tendency to answer in “a certain direction”. • Conscious or unconscious misrepresentation • Types: • 1. Deliberate falsification (why?)
Why would people deliberately falsify data • Appear to be what they are not • Don’t trust confidentiality • Protect • To end the interviewer quicker • “Average man effects”
Types of response bias continued: • 1. Deliberate falsification • 2. Unconscious misrepresentation
Reasons for unconscious misrepresentation: • Question format • Question content • Misunderstanding of question leading to biased answer • Lack of time to consider answer fully • Communication or semantic confusion • other
Types of response bias • Acquiescence bias: individuals have a tendency to agree or disagree with all questions or to indicate a positive/negative connotation • Extremity bias: results for response styles varying from person to person; some people tend to use extremes when responding to questions
Types of response bias continued... • Interviewer bias: Bias in the responses of the subject due to the influence of the interviewer • Auspices bias: respondents being influenced by the organization conducting the study • Social desirability bias: caused by respondents’ desire, either consciously or unconsciously to gain prestige or to appear in a different social role