Before conducting a study it is often a good idea to decide on the necessary sample size. To do so, statisticians often first decide on an acceptable margin of error and then work backward to the sample size. Since they haven't run the study yet it is common practice to approximate the sample proportion as 50% since this is the worst case scenario. (a) If researchers decide on a 4.7% margin of error for a 95% confidence interval. What sample size should they pursue?  (b) If researchers decide on a 2.6% margin of error for a 99% co

Q: Suppose the NCES would like to re-do their study. If they want a 95% confidence interval with a…

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Q: Suppose we have two normal populations denoted A and B, and we want to compare their population…

A: Let the sample variance of A be SA2, the according to question the variance of B will be…

Q: If you need to make a 98% confidence interval for a proportion, and the margin of error is to be no…

A: Given information:  Confidence level = 98% Margin of error (e) = 0.025 Let proportion (p) = 0.5 The…

Q: C. If one is constructing a confidence interval for the mean and the level is 90%, then each tail…

A: c) The confidence level is 0.90.

Q: A political candidate has asked his/her assistant to conduct a poll to determine the percentage of…

A: Given E=0.04 Alpha=0.05

Q: Before making decisions about changing branch manager salaries the bank wants to estimate average…

A:

Q: A sociologist wants to construct a 94% confidence interval for the proportion of teenagers who uses…

A: Given, p=0.23 E=0.02 z value at 94% confidence is Zc=1.88 n=?

Q: A researcher wants to estimate the proportion of electric car owners in Los Angeles County. The…

A: According to the given information, we havePopulation proportion, p = 10% = 0.10Margin of error, E =…

Q: For the same sample proportion and sample size, what happens to the width of a confidence interval…

A: Solution-: For the same sample proportion and sample size, what happens to the width of a confidence…

Q: Kim wants to determine a 80 percent confidence interval for the true proportion of high school…

A: Given: Margin of error, E=0.04 Confidence level=80%

Q: determining if her new technique for improving players' golf scores is effective.  She takes 4 new…

A: Independent sample means with population standard deviations unknown

Q: If Xbar=81​,S=20​,and n=36​,and assuming that the population is normally​ distributed, construct a…

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Q: For a research, let's consider the 10-unit sample with s = 32,866 as a preliminary example. For a…

A: Given data,s=32866E=10z-value at 95% confidence is Zc=1.96n=?

Q: The mean height of women in a country (ages 20 - 29) is 64.1 inches. A random sample of 55 women in…

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Q: Increasing the sample size and decreasing the level of confidence are two ways of obtaining a…

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Q: Call me: A sociologist wants to construct a 95% confidence interval for the proportion of children…

A: Given confidence level, C = 95% = 0.95 Level of significance, α = 1-0.95 = 0.05 Using formula,

Q: What is the impact on the confidence interval estimate if a larger sample is used?

A: Confidence interval:

Q: 1. California is the most populated state with a population of 38,332,521 (as reported by the U.S.…

A: Given information: Margin of Error=3.5% points=0.035 Confidence level=95% Significance level=5%=0.05…

Q: Suppose that we wanted to estimate the true average number of eggs a queen bee lays with 99%…

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Q: How large would the sample need to be so that a 95% confidence interval would have a margin of…

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Q: students. You want to estimate the proportion p of students who never floss with 90% confidence and…

A: It is given that Proportion p = 0.27 Margin of error E = 0.03 Level of confidence = 90% The critical…

Q: You want to estimate the difference between two population means using a 95% confidence interval.…

A: Given  Margin of Error (ME) = 0.6 The sample size of first population will be 100.

Q: What should your sample size be if you want a confidence level of 90 percent and a margin of error…

A: We want to find the sample size (n)

Q: You are trying to calculate a confidence interval to estimate a population mean. After performing…

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Q: the sample size required to limit the margin of error to within 0.031 of the population proportion…

A: Given : Margin of error: ME = 0.031

Q: There is a popular lottery in which a ticket is called a scratcher. You are an auditor and want to…

A:

Q: If no previous study has been done, give the sample size we should use to find p with a margin of…

A: Given that, Critical value: Using the z-table, the critical value at 90% confidence level for two…

Q: The width of a confidence interval is a measure of its precision. The narrower the confidence…

A: The width of the confidence interval of a single population mean can be calculated using the…

Q: Estimate 95% confidence interval for the proportion of household experiencing burglary in 2010."

A: 25.8 households per 1,000 were the victims of home burglary. These data are obtained from a survey…

Q: Let's change our scenario a little. Suppose that a scientist wants to construct a 95% confidence…

A: Given : n1 = 112 x1 = 56 n2 = 107 x2 = 73

Q: f you wish to estimate a population mean with a sampling distribution error SE= 0.28 using a 95%…

A:

Q: briefly describe the difference between estimation and hypothesis testing.

A: It is needed to discuss about the difference between estimation and hypothesis testing.

Q: ou are a manager for a local convenience store. You want to determin proportion of your customers…

A: Given that  Margin of error =E=6.50%=0.0650 99% confidence.

Q: You have 16 vampire bats. These bats have a population variance of 3.4 ounces. You wish to make a…

A: Given: Sample size (n) = 16 Population variance σ2=3.4 Sample mean x¯=15.20 Confidence level = 0.950

Q: Cora wants to determine a 90% confidence interval for the true proportion of high school students in…

A: Confidence level=90%Margin of error(E)=0.02Assuming that we have no prior estimate of the proportion…

Q: Sample information: 24 out of 1000 people who were surveyed had type 2 diabetes. Use the above…

A: Given n=1000 x=24

Q: Many medical professionals believe that smoking increases the risk of heart disease and cancer. A…

A: From the given information, it is obtained that: σ (population standard deviation)=12Confidence…

Q: If N=480 and p̂ (p-hat) =0.88, find the margin of error at a 95% confidence level.

A: From the provided information, Sample size (n) = 480 p̂ (p-hat) =0.88 Confidence level = 95%

Q: Find the sample size of American adults you would need to predict the results of an election with a…

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Q: Ve want to know how many people plan on buying a cell phone this year. Determine the sample size…

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Q: You want to survey students to see what proportion of them have taken Statistics 101. This survey…

A: Margin of error(M) = 4% = 0.04 Confidence interval = 95%

Estimation

A new framework of data analysis where the new statistical methods are used for interpreting the results and analyzing the data is known as estimation in statistics.