In 2008 and 2017 a poll asked Democratic voters about their views on the FBI. In 2003, 45% thought the FBI did a good or excellent job. In 2017, 74% of Democratic voters felt this way. Assume these percentages are based on samples of 800 Democratic voters. Complete parts (a) through (d) below. a. Can we conclude, on the basis of these two percentages alone, that the proportion of Democratic voters who think the FBI is doing a good or excellent job has increased from 2003 to 2017? Why or why not? OA. Yes. Since a lesser percentage is present in the sample, a lesser percentage of Democratic voters who think the FBI is doing a good or excellent job is present in the population. B. No. Although a lesser percentage is present in the sample, the population percentages could be the same or even reversed. OC. No. Since a greater percentage is present in the sample, we cannot conclude that a lesser percentage of Democratic voters who think the FBI is doing a good or excellent job is present in the population. OD. No. Although a lesser percentage is present in the sample, the population percentages could be the same, but could not be reversed. b. Check that the conditions for using the two-proportion confidence interval hold. You can assume that the sample is a random sample. The Random and Independent condition holds, assuming a random sample. The Large Samples condition holds. The Big Populations condition can reasonably be assumed to hold. The Independent Samples condition holds. c. Construct a 95% confidence interval for the difference in the proportions of Democratic voters who believe the FBI is doing a good or excellent job, p₁ - P2. Let p, be the proportion of Democratic voters who felt this way in 2003 and p2 be the proportion of Democratic voters who felt this way in 2017. The 95% confidence interval is (.). (Round to three decimal places as needed.)
In 2008 and 2017 a poll asked Democratic voters about their views on the FBI. In 2003, 45% thought the FBI did a good or excellent job. In 2017, 74% of Democratic voters felt this way. Assume these percentages are based on samples of 800 Democratic voters. Complete parts (a) through (d) below. a. Can we conclude, on the basis of these two percentages alone, that the proportion of Democratic voters who think the FBI is doing a good or excellent job has increased from 2003 to 2017? Why or why not? OA. Yes. Since a lesser percentage is present in the sample, a lesser percentage of Democratic voters who think the FBI is doing a good or excellent job is present in the population. B. No. Although a lesser percentage is present in the sample, the population percentages could be the same or even reversed. OC. No. Since a greater percentage is present in the sample, we cannot conclude that a lesser percentage of Democratic voters who think the FBI is doing a good or excellent job is present in the population. OD. No. Although a lesser percentage is present in the sample, the population percentages could be the same, but could not be reversed. b. Check that the conditions for using the two-proportion confidence interval hold. You can assume that the sample is a random sample. The Random and Independent condition holds, assuming a random sample. The Large Samples condition holds. The Big Populations condition can reasonably be assumed to hold. The Independent Samples condition holds. c. Construct a 95% confidence interval for the difference in the proportions of Democratic voters who believe the FBI is doing a good or excellent job, p₁ - P2. Let p, be the proportion of Democratic voters who felt this way in 2003 and p2 be the proportion of Democratic voters who felt this way in 2017. The 95% confidence interval is (.). (Round to three decimal places as needed.)
MATLAB: An Introduction with Applications
6th Edition
ISBN:9781119256830
Author:Amos Gilat
Publisher:Amos Gilat
Chapter1: Starting With Matlab
Section: Chapter Questions
Problem 1P
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Part c?
The 95% confidence interval is?
(Round to three decimal places)
Transcribed Image Text:In 2008 and 2017 a poll asked Democratic voters about their views on the FBI. In 2003, 45% thought the FBI did a good or excellent job. In 2017, 74% of Democratic voters felt this way. Assume
these percentages are based on samples of 800 Democratic voters. Complete parts (a) through (d) below.
a. Can we conclude, on the basis of these two percentages alone, that the proportion of Democratic voters who think the FBI is doing a good or excellent job has increased from 2003 to 2017? Why
or why not?
OA. Yes. Since a lesser percentage is present in the sample, a lesser percentage of Democratic voters who think the FBI is doing a good or excellent job is present in the population.
B. No. Although a lesser percentage is present in the sample, the population percentages could be the same or even reversed.
OC. No. Since a greater percentage is present in the sample, we cannot conclude that a lesser percentage of Democratic voters who think the FBI is doing a good or excellent job is present in
the population.
OD. No. Although a lesser percentage is present in the sample, the population percentages could be the same, but could not be reversed.
b. Check that the conditions for using the two-proportion confidence interval hold. You can assume that the sample is a random sample.
The Random and Independent condition holds, assuming a random sample.
The Large Samples condition holds.
The Big Populations condition
can
reasonably be assumed to hold.
The Independent Samples condition holds.
c. Construct a 95% confidence interval for the difference in the proportions of Democratic voters who believe the FBI is doing a good or excellent job, p₁ - P2. Let p, be the proportion of Democratic
voters who felt this way in 2003 and p2 be the proportion of Democratic voters who felt this way in 2017.
The 95% confidence interval is (.).
(Round to three decimal places as needed.)
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