Question 2:
Explain the meaning of a point estimate and an interval estimate.
a. The value of a sample statistic used to estimate a population parameter is called an interval estimate. A point estimate is an interval that is constructed around the interval estimate, and it is stated that this interval is likely to contain the corresponding population parameter.
b. A point estimate is a population parameter used in calculations while an interval estimate is an interval that is constructed around the point estimate, and it is stated that this interval is likely to contain the corresponding population parameter.
c. The value of a sample statistic used to estimate the standard deviation is an interval estimate, and a point estimate is the value of a sample statistic used to estimate the mean.
d. The value of a sample statistic used to estimate a population parameter is called a point estimate. In interval estimation, an interval is constructed around the point estimate, and it is stated that this interval is likely to contain the corresponding population parameter.
e. The value of a sample statistic used to estimate the mean is an interval estimate, and a point estimate is the value of a sample statistic used to estimate the standard deviation.
Question 3:
For a data set obtained from a sample of size n = 144 with it is known that σ = 5.6.
(a) What is the point estimate of µ?
µ =
(b) Find z score corresponding to a 95% confidence level, zα/2. Recall that (1 − α)100% = 95%.
Give your answer with two decimal places.
z =
(c) Construct a 95% confidence interval for µ.
Round the answers to four decimal places.
< µ <
(d) What is the margin of error in part (c)?
Round the answer to four decimal places.
E =
Question 4:
Consider versus
A random sample of 35 observations taken from this population produced a sample mean of 40.29. The population is normally distributed with
Calculate the p-value. Round your answer to four decimal places.
Question 5:
For a data set obtained from a sample, n=81 and x¯=49.55. It is known that σ=4.0. a. What is the point estimate of μ? The point estimate is . b. Make a 90% confidence interval for μ. Round your answers to two decimal places. (,
) c. What is the margin of error of estimate for part b? Round your answer to three decimal places. E=
Question 6:
The standard deviation for a population is σ=14.1. A sample of 21 observations selected from this population gave a mean equal to 143.55. The population is known to have a normal distribution. Round your answers to two decimal places. a. Make a 99% confidence interval for μ. (,
) b. Construct a 95% confidence interval for μ. (
,
) c. Determine a 90% confidence interval for μ. (
,
) d. Does the width of the confidence intervals constructed in parts a through c decrease as the confidence level decreases?
Question 7:
Which of the following is a two-tailed test?
| H0: μ=38, H1: μ≠38 |
| H0: μ=187, H1: μ<187 |
| H0: μ=70, H1: μ>70 |
Question 8:
Find the p-value for the following hypothesis test.
H0: μ=19, H1: μ≠19, n=81, x¯=18.00, σ=6.3
Round your answer to four decimal places.
p=
Question 9:
Find the p-value for the following hypothesis test.
H0: μ=20, H1: μ<20, n=49, x¯=18.00, σ=5.6
Round your answer to four decimal places.
p=
Question 10:
Consider H0: μ=38 versus H1: μ>38. A random sample of 35 observations taken from this population produced a sample mean of 40.29. The population is normally distributed with σ=7.2.
Calculate the p-value. Round your answer to four decimal places.
p=
