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Sample Size Determination

Determining appropriate sample sizes

Why is it important to determine an appropriate sample size and how can you determine what sample size you should use to ensure that your population mean (mu) is within your confidence interval?

A sample of 12 homes sold last week in St. Paul, Minnesota, is selected...

A sample of 12 homes sold last week in St. Paul, Minnesota, is selected. Can we conclude that as the size of the home (reported below in thousands of square feet) increases, the selling price (reported in $ thousands) also increases? Home Size Selling (thousands Price of square feet) ($ thousands)

Sample Size for 95% Confidence

Problem (also attached): 1) An Entomologist wishes to estimate the average development time of the citrus red mite correct to within .5 day. From previous experiments it is known that standard deviation is in the neighborhood of 4 days. How large a sample should the entomologist take to be 95% confident of her estimate.

Sample size for a proportion

Using the large database of survey responses (this is your sample - see attached), you will begin testing hypotheses. Complete the following: 6. Determine the required sample size if you need to estimate the number of workers in the United States who are highly satisfied with their job and you want the estimate to be within

To estimate the proportion of Republicans in favor of the bill, how large must a sample of representatives be to estimate the percentage within 3 percentage points with 90% certainty.

The house of representatives has a very controversial bill that will be going to vote. To help formulate his strategy on how to get the bill passed, the chairman of the committee that has been studying the bill wishes to know if there is a division between Democrats and Republicans on the issue or if there is some other basis f

Sample size

Z= .49 confidence level e= 10.00 desired margin of error 0= 500 population standard deviation I can't make the Greek letter for the last one so I used o which is the close to the o with a line I need to know what the sample size will be with this information.

Important information about Sample size needed to estimate a population mean.

Suppose that a researcher is interested in estimating the mean systolic blood pressure of executives of major corporations. He plans to use the blood pressures of a random sample of executives of major corporations to estimate the population mean. Assuming that the standard deviation of the population of systolic blood pressures

General stats problem

Question 4 (20 Points): A marketing survey is to be planned to estimate the proportion of all customers who would subscribe to a new pay-per-view service that a cable TV plans to offer. The sample size for the survey is to be decided to estimate this proportion within a margin of error 2 percentage of points using a 95% confiden

Finding Minimum Sample Size

A survey of shoppers is planned to determine what percentage use credit cards. Prior surveys suggest that 59% use credit cards. The required margin of error is 0.02 at 95% confidence. What is the minimum sample size required to assure that your sample proportion "p" will be within the required margin of error, around the popul