6. We want to determine the sample size for estimating the population proportion p that would...
8. (9 pts) Suppose that we want to construct a 95% confidence interval to estimate the percentage of voters who would vote a candidate. We suggest that approximately 46% would vote for the candidate. Suppose that we want the margin of error for the confidence interval is no more than 1%. Determine how large the sample size should be.
a. Assume that a sample is used to estimate a population proportion p. Find the 95% confidence interval for a sample of size 198 with 42 successes. Enter your answer as an open-interval (i.e., parentheses) using decimals (not percents) accurate to three decimal places. 95% C.I. = b. A political candidate has asked you to conduct a poll to determine what percentage of people support her. If the candidate only wants a 0.5% margin of error at a 99% confidence...
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...
Determine the sample size needed in forming a 95% confidence interval for a proportion with margin of error of 0.04. (Use the “safe approach” for the population proportion (i.e., p=.50) Repeat part a.) for a margin of error of 0.02.
Suppose we are interested in estimating the proportion of a population using a simple random sample of size n. i. State a suitable estimator of the population proportion as well as its sampling distribution. Mention any assumptions which you make. ii. Explain statistically how to determine the minimum sample size necessary to estimate a population proportion to within e units. iii. Provide a practical marketing example of a 95% confidence interval for a proportion. iv. Explain the purpose of the...
that corresponds to the Assume that a sample is used to estimate a population proportion p. Find the margin of error E given statistics and confidence level. Round the margin of error to four decimal places. 48) 50 B) 0.0306 48) 95% confidence, n-380. x C) 0.0357 D) 0.0340 A) 0.0408 Objective: 7.2) Find Margin of Error Use the given degree of confidence and sample data to construct a confidence interval for the population proportionp. 49) 49) n = 56,...
5. (5 pts) Find the minimum sample size n necessary to estimate a population proportion p with a 95% confidence interval that has a margin of error m = 0.05. Assume that you don’t have any idea what p is so that you use the simpler formula for n (which comes from taking the more complicated formula for n and substituting p ∗ = 0.5 into it).
Recall the formula for a proportion confidence interval is p^?zp^(1?p^)n?????????<p<p^+zp^(1?p^)n????????? Thus, the margin of error is E=zp^(1?p^)n????????? . NOTE: the margin of error can be recovered after constructing a confidence interval on the calculator using algebra (that is, subtracting p^ from the right endpoint.) In a simple random sample of size 59, taken from a population, 20 of the individuals met a specified criteria. a) What is the margin of error for a 90% confidence interval for p, the population...
1. Find the sample size needed to estimate the proportion of houses that have security systems if the sample proportion h = 0.19, the margin of error is 0.02, and the confidence level is 90%. 2. Suppose that in a random sample of 50 adults, 41 were registered to vote. Construct a 95% confidence level interval for the population proportion of registered voters.
Using the Formula n=1/(ME)2 to Determine Sample Size When we want 95 % confidence and use the conservative estimate of p = 0.5 , we can use the simple formula n = 1 M E 2 to roughly determine the sample size needed for a given margin of error M E . Use this formula to determine the sample size needed for a margin of error of 0.04 . Enter the exact answer.