Concept explainers
Telephone pollsters often interview between 1000 and 1500 individuals regarding their opinions on various issues. Does the performance of colleges’ athletic teams have a positive impact on the public’s perception of the prestige of the institutions? A new survey is to be undertaken to see if there is a difference between the opinions of men and women on this issue.
a If 1000 men and 1000 women are to be interviewed, how accurately could you estimate the difference in the proportions who think that the performance of their athletics teams has a positive impact on the perceived prestige of the institutions? Find a bound on the error of estimation.
b Suppose that you were designing the survey and wished to estimate the difference in a pair of proportions, correct to within .02, with probability .9. How many interviewees should be included in each sample?
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Chapter 8 Solutions
Mathematical Statistics with Applications
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