1) A random sample of size 15 taken from a normally distributed population revealed a sample mean of 75 and a sample variance of 25. The upper limit of a 95% confidence interval for the population mean would equal?

2. Based on sample data the 90% confidence interval limits forth population mean are 170.86 and 195.42. If the 10% level of significance was used in testing the hypthesis H1o:u=201, H1" u = 201 the null hypothesis:

would be rejected
would not be rejected
would have to be revealed
none of the above

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1) a random sample of size 15 taken from a normally distributed population revealed a sample mean of 75 and a sample variance of 25. The upper limit of a 95% confidence interval for the population mean would equal?

Sample standard deviation=square root of Variance=square root of 225= 15

Assume that in a hypothesis test with nullhypothesis H 0: mu = 14.0 at alpha = 0.05, that a value of 13.0 for the sample mean results in the nullhypothesis being rejected. That corresponds to a confidence interval result of:
a) the 95% confidence interval for the mean contains the value 14.0
b) the 95% confidence interval

Assume that in a hypothesis test with nullhypothesis = 13.0 at 0.05, that a value of 11.0 for the sample mean results in the nullhypothesis not being rejected. That corresponds to a confidence interval result of
A. The 95% confidence interval for the mean does not contain the value 13.0
B. The 95% confidence interval for

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The Osborne manufacture makes a soft drink dispensing machine that allows customers to get soft drinks from the machine in a cup with ice. When the machine is running properly, the average number of fluid ounces in the cup should be 14. Periodically the machines need

A confidence interval for the population mean tells us which values of mean are plausible (those inside the interval) and which values are not plausible (those outside the interval) at the chosen level of confidence. You can use this idea to carry out a test of any nullhypothesis. Ho:mean =Mo starting with a confidence interva

1. What are the null and alternate hypotheses for this test? Why?
2. What is the critical value for this hypothesis test using a 5% significance level?
3. Calculate the test statistic and the p-value using a 5% significance level.
4. State the decision for this test.
5. Determine the confidence interval level that would be a

What is the relationship between a confidence interval and a single sample, two-tailed hypothesis test?
How are they the same? How are they different?
Review the definition of a single sample, two tailed test. Now review the structure of a confidence interval.
What are the assumptions and requirements for the use

Consider the following Hypothesis Testing:
H0: δ1² = δ2²
Ha: δ1² ≠ δ2²
The sample size for sample 1 is 25, and for sample 2 are 21. The variance for sample 1 is 4.0 and for sample 2 is 8.2
a) at the confidence level of 0.98, what is your conclusion of this test?
b) What is the confidence

Suppose a regression output produces the following 99% confidence interval for one regression coefficients: [-32.47,-16.88]
Given this information, should an analyst reject the nullhypothesis that this population regression coefficient is equal to 0? Explain your answer.