Question

1. Based on the CLT if the population sigma = 200 and the number of data samples collected is 4, the estimated standard deviation of the sample standard deviation will equal:

2. A sample of 200 widgets was sampled for defects and determined to be normally distributed. If the population standard deviation=2 and Xbar=7 you estimate the Upper Confidence interval at 95% confidence level to equal ? Given K=1.96

3. In Hypothesis testing a Type 1 error is defined as: a) alpha risk, b)beta risk, c) power, d) 1- beta, e) 1- alpha

4. If the sample data set distribution is symmetric, and n= 10 then the following statement is true: a) we can apply the CLT, b) we can apply the CLP, c) we can apply the USL, d) we can apply the LSL

5. When performing a 2-sample t- Test the statement: X1=X2 can be classified as: a) Ho, b) Hp, c) Ha, d) Hc

Answer #1

If x1,x2,...xn denote all the values from the population, then (population) standard deviation sigma is given by

Where is the mean of population.

If x1,x2,...xn denote all the values from the sample, then (sample) standard deviation s is given by

Where is sample mean;

Now we have popuation standard deviation given . we can calculate sample standard deviation from following formula.

so .

The population size is not given in question, insert it and you will get the answer.

§ 1 Central Limit Theorem (CLT)
1. The CLT states: draw all possible samples of size
_____________ from a population.
The result will be the sampling distribution of the means will
approach the ___________________-
as the sample size, n, increases.
2. The CLT tells us we can make probability statements about the
mean using the normal distribution even though we know
nothing about the ______________-
3.
The standard error of the mean is
the ___________ of the sampling distribution of the...

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what is the left end point of a back-of-the-envelope 95%
confidence interval for the population mean?
___________________________________________
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Obtain a 95% confidence interval for the difference between the
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mean will be used to estimate the population mean.
a. What is the expected value of the sample mean?
b. What is the standard deviation of the sample mean?
c. Confirm whether the Central Limit Theorem is met and explain
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d. Draw the sampling distribution of the sample mean.
e. What...

1. A cigarette manufacturer claims that one-eighth of the US
adult population smokes cigarettes. In a random sample of 100
adults, 5 are cigarette smokers. Test the manufacturer's claim at
alpha= 0.05. (critical values of z are ±
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phone call is 8 minutes. In a random sample of 58 phone calls, the
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1.)
You want to obtain a sample to estimate a population mean. Based
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2.)
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1. To estimate the mean of a population with unknown
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