a) The sample proportion is:
For 95% confidence level, critical value of z is .
The 95% confidence interval for p is:
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b) For 99% confidence level, critical value of z is .
The 99% confidence interval for p is:
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c) 99% confidence interval is wider than 95% confidence interval.
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d) There is 95% probability that p is contained in any interval, and since each survey is independent then the probability that the true value of p is contained in all 20 intervals is:
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e) We expect 0.95 of 20 samples containing p value, that is:
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f) For 95% confidence level, critical value of z is .
The given margin of error is . The required sample size is:
In a survey of 500 likely voters, 271 responded that they would vote for the incumbent...
In a survey of 500 likely voters, 271 responded that they would vote for the incumbent and 229 responded that they would vote for the challenger. Let pp denote the fraction of all likely voters who preferred the incumbent at the time of the survey, and let p^p^ be the fraction of survey respondents who preferred the incumbent. a. Use the survey results to calculate p^p^. b. Test the hypothesis H0:p=0.5 vs. Ha:p≠0.5H0:p=0.5 vs. Ha:p≠0.5 at the 5% significance level....
20 pts] In a survey of 400 likely voters, 215 responded that they would vote for the incumbent and 185 responded that they would vote for the challenger. Let p denote the fraction of all likely voters who preferred the incumbent at the time of the survey, and let p be the fraction of survey respondents who preferred the incumbent. (g) Construct a 95% confidence interval for p. (h) Construct a 99% confidence interval for p. (i) Why is the...
(2) 120 pts] In a survey of 400 likely voters, 215 responded that they would vote for the incumbent and 185 responded that they would vote for the challenger. Let p denote the fraction of all likely voters who preferred the incumbent at the time of the survey, and let p be the fraction of survey respondents who preferred the incumbent. (a) Use the survey results to estimate p. (b) Use the estimator of the variance of p, p(1 -p)/n,...
show your workings In a survey of 400 likely voters, 213 responded that they would vote for the incumbent and 187 responded that they would vote for the challenger. Let p denote the fraction of all likely voters who preferred the incumbent at the time of the survey, and lot be the fraction of survey respondents who preferred the incumbent. Using the survey to the estimated value of pis 0.5325. Round your response to four decimal places.) Using Pt-pyn as...
A polling firm called 1,000 likely voters to ask about their political preferences. Of those polled, 520 indicated that they would vote for the incumbent candidate. Determine the point estimate for the proportion of voters in the election district who will vote for the incumbent.What is the sampling distribution for p in this example?Approximately how many voters must be polled for a margin of error equal to .01, assuming a confidence level of 95%? Show your work.
In a random sample of 100 registered voters, 20 say they plan to vote for Candidate A.Determine a 95% confidence interval for the proportion of all the registered voters who will vote for Candidate A.You are interested in knowing support for candidate by gender to provide strategic advice to candidate B. Suppose your guess based on previous knowledge is that female support for candidate B is around 20 percent, and male support for candidate B is around 50 percent. Suppose...
A sample of 1000 likely voters is taken and 53% indicate that they will vote for candidate Z. Calculate a 95% confidence interval estimate for the proportion of the population that will vote for Candidate Z (or the value p).
We are interested in conducting a study in order to determine what percentage of voters of a state would vote for the incumbent governor. What is the minimum size sample needed to estimate the population proportion with a margin of error of 0.04 at 95% confidence? Use a planning value of p∗= 0.5. a. 601 b. 600 c. 385 d. 307
38. A congressional candidate is running for reelection. In a recent poll of 900 registered voters, 510 said that they will vote for the candidate in the upcoming election. (round your answers to four decimal places) part a: Calculate and report the sample proportion part b: Calculate and report the margin of error for this poll for a 95% confidence interval. part c: Calculate and report the 95% confidence interval for the population proportion of registered voters who will vote...
A random sample of ikely voters showed that 64 % planned to vote for Candidate X, with a margin of eror of 1 percentage points and with 95 % confidence, a. Use a carefully worded sentence to report the 95 % confidence interval for the percentage of voters who plan to vote for Candidate X b. Is there evidence that Candidate X could lose? c. Suppose the survey was taken on the streets of a particular city and the candidate...