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Unformatted text preview: ethod for selecting the participants produces a sample that does not represent the population of interest. Nonparticipation bias (nonresponse bias) occurs when a representative sample is chosen for a survey, but a subset cannot be contacted or does not respond. Biased response or response bias occurs when participants respond differently from how they truly feel. The way questions are worded, the way the interviewer behaves, as well as many other factors might lead an individual to provide false information. Try It! Exercise 5.16 (page 177) Which type of bias do you think would be introduced if … d. A magazine sends a survey to a random sample of its subscribers asking them if they would like the frequency of publication reduced from biweekly to monthly, or would prefer that it remain the same. Nonresponse – some will not send back survey. Those who feel more strongly about the issue generally respond. e. A random sample of registered voters is contacted by phone and asked whether or not they are going to vote in the upcoming presidential election. Response bias – most people will say YES even if they are not likely to vote; they don’t want to ‘sound unpatriotic’. 5.2 Margin of Error, Confidence Intervals, and Sample Size Sample surveys are often used to estimate the proportion or percentage of all people who have...
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This document was uploaded on 02/25/2014 for the course STATS 250 at University of Michigan.
- Summer '10