When constructing confidence intervals for population means, an analyst must never use personal judgement to estimate

When constructing confidence intervals for population means, an analyst must never use personal judgement to estimate a preliminary value of the population standard deviation when attempting to select a sample size for desired margin of error. Calculations must be used for the preliminary value estimate.

True

False

Solutions

Expert Solution

The sample size is computed from the margin of error as:

A prior estimate of the population standard deviation is used to get the sample size from the above formula instead of using any personal judgement. Otherwise we may get a less conservative sample size or very high conservative sample size for the test.

orchestra answered 1 year ago

Next > < Previous

Related Solutions

Confidence Intervals for Population Means When the Population Standard Deviation is Unknown. Use the table of...

Confidence Intervals for Population Means When the Population Standard Deviation is Unknown. Use the table of critical values of t to find the following: Construct a confidence interval for the population mean at the given confidence level. Remember to find your degrees of freedom. 4. n = 25, x = 56, s = 8, level of confidence is 95% 2 5. n = 36, x = 23.6 s = 4.2 level of confidence is 90% 6. Level of confidence is...

In constructing 95% confidence interval estimate for the difference between the means of two populations, where...

In constructing 95% confidence interval estimate for the difference between the means of two populations, where the unknown population variances are assumed not to be equal, summary statistics computed from two independent samples are: ?1=45,?̅1=756,?1=18,?2=40,?̅2=762,?2=15 (using 2-sample T menu) a. Calculate the 95% confidence interval for the true difference of two means. b. Base on the interval in the previous question, can one conclude there is a difference in means of two populations? Justify your answer.

Constructing and Interpreting Confidence Intervals. In Exercises 13–16, use the given sample data and confidence level....

Constructing and Interpreting Confidence Intervals. In Exercises 13–16, use the given sample data and confidence level. In each case, (a) find the best point estimate of the population proportion p; (b) identify the value of the margin of error E; (c) construct the confidence interval; (d) write a statement that correctly interprets the confidence interval. Medical Malpractice In a study of 1228 randomly selected medical malpractice lawsuits, it was found that 856 of them were dropped or dismissed (based on...

NEED NEW ANSWER Consider when businesses might use confidence intervals to estimate values, such as in...

****NEED NEW ANSWER**** Consider when businesses might use confidence intervals to estimate values, such as in sales projections, marketing results, and so forth. Describe a business decision that could be helped with confidence intervals. Be specific! Then create a problem with numbers from which another student could calculate a confidence interval and make a decision

Consider when businesses might use confidence intervals to estimate values, such as in sales projections, marketing...

Consider when businesses might use confidence intervals to estimate values, such as in sales projections, marketing results, and so forth. Describe a business decision that could be helped with confidence intervals. Be specific! Then create a problem with numbers from which another student could calculate a confidence interval and make a decision.

Confidence Intervals – Means & Proportions 1. You would like to estimate the starting salaries...

Confidence Intervals – Means & Proportions 1. You would like to estimate the starting salaries of recently graduated business majors (B.S. in any business degree). You randomly select 60 recently graduated business majors and get a sample mean of $43,800 and the population standard deviation is known to be $8,198 A. Construct a 90% confidence interval to estimate the average starting salary of a recently graduated business major (Round to the nearest penny and state the answer as...

Constructing Confidence Intervals In Exercises 45 and 46, use the information to construct 90% and 99%...

Constructing Confidence Intervals In Exercises 45 and 46, use the information to construct 90% and 99% confidence intervals for the population mean. Interpret the results and compare the widths of the confidence intervals. 45. DVR and Other Time-Shifted Viewing A group of researchers estimates the mean length of time (in minutes) the average U.S. adult spends watching television using digital video recorders (DVRs) and other forms of time-shifted television each day. To do so, the group takes a random sample...

How do you know when to check normality or indepencence when constructing confidence intervals for proportions...

How do you know when to check normality or indepencence when constructing confidence intervals for proportions and means?

Use the following information to construct the confidence intervals specified to estimate μ. a. 95% confidence...

Use the following information to construct the confidence intervals specified to estimate μ. a. 95% confidence for x ¯ = 22, σ = 3.5, and n = 55 b. 98% confidence for x ¯ = 120.6, σ = 28.89, and n = 67 c. 90% confidence for x ¯ = 2.419, σ = 0.888, and n = 29 d. 80% confidence for x ¯ = 56.7, σ = 9.1, N = 500, and n = 47

Use the following information to construct the confidence intervals specified to estimate μ. a. 95% confidence...

Use the following information to construct the confidence intervals specified to estimate μ. a. 95% confidence for = 26, σ = 4.5, and n = 57 b. 98% confidence for = 115.6, σ = 21.89, and n = 79 c. 90% confidence for = 3.419, σ = 0.876, and n = 31 d. 80% confidence for = 55.7, σ = 14.1, N = 500, and n = 43

Subjects