Equal Variances: (-10.6751,4.0751)

asked 2021-06-20

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. 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 of 30 U.S. adults and obtains the times (in minutes) below.
29 12 23 24 33 24 28 31 18 27 27 32 17 13 17 12 21 32 26 16 28 28 21 24 29 13 20 13 21 27
From past studies, the research council assumes that σσ is 6.5 minutes.

asked 2021-05-09

a. What is the value of the sample mean resonance frequency?

b. The confidence level for one of these intervals is 90%90%and for the other it is 99%99%. Which is which, and how can you tell?

asked 2021-06-12

For each of the following confidence intervals for the difference between two means,

\((\mu_{1}-\mu_{2})\)

which mean is significantly larger?

a.(-10.5)

b.(-10,-5)

c.(5,10)

asked 2021-05-26

You are given the sample mean and the population standard deviation. Use this information to construct 90% and 95% confidence intervals for the population mean. Interpret the results and compare the widths of the confidence intervals. From a random sample of 36 business days from February 24, 2016, through February 24, 2017, the mean closing price of Apple stock was $116.16. Assume the population standard deviation is $10.27.

asked 2021-06-01

(a) What is the value of c\(\displaystyle{c}={1}-\alpha\);. Using the methods, construct a \(\displaystyle{c}={1}-\alpha\); confidence interval for μ from the sample data. What is the value of \(\mu\); given in the null hypothesis (i.e., what is k)? Is this value in the confidence interval? Do we reject or fail to reject \(H_0\) based on this information?

(b) using methods, find the P-value for the hypothesis test. Do we reject or fail to reject \(H_0\)? Compare your result to that of part (a).

asked 2021-07-04

asked 2021-05-16