MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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Influencing Voters
When getting voters to support a candidate in an election, is there a difference between a recorded phone call from the candidate or a flyer about the candidate sent through the mail? A sample of 500 voters is randomly divided into two groups of 250 each, with one group getting the phone call and one group getting the flyer. The voters are then contacted to see if they plan to vote for the candidate in question. We wish to see if there is evidence that the proportions of support are different between the two methods of campaigning.
(a) State the null and alternative hypotheses. Your answer should be an expression composed of symbols: =,≠,<,>,μ,μ1,μ2,p,p1,p2,ρ,p^,p^1,p^2,r.
Let group 1 be the supporters of Candidate A after a phone call and let group 2 be the supporters of Candidate A after a flyer.
(a) State the null and alternative hypotheses. Your answer should be an expression composed of symbols: =,≠,<,>,μ,μ1,μ2,p,p1,p2,ρ,p^,p^1,p^2,r.
Let group 1 be the supporters of Candidate A after a phone call and let group 2 be the supporters of Candidate A after a flyer.
(b) Possible sample results are shown in Table 1.
Compute the two sample proportions: p^1, the proportion of voters getting the phone call who say they will vote for the candidate, and p^2 , the proportion of voters getting the flyer who say they will vote for the candidate.
Enter the exact answers.
Compute the two sample proportions: p^1, the proportion of voters getting the phone call who say they will vote for the candidate, and p^2 , the proportion of voters getting the flyer who say they will vote for the candidate.
Enter the exact answers.
Is there a difference in the sample proportions?
(c) A different set of possible sample results are shown in Table 2.
Compute the same two sample proportions for this table.
Enter the exact answers.
Compute the same two sample proportions for this table.
Enter the exact answers.
(d) Which of the two samples seems to offer stronger evidence of a difference in effectiveness between the two campaign methods?
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