Question

The following table contains information on matched sample values whose differences are normally distributed.

Number	Sample 1	Sample 2
1	17	20
2	12	12
3	21	22
4	21	20
5	16	21
6	14	16
7	17	18
8	17	20

a. Construct the 90% confidence interval for the mean difference μ_D. (Negative values should be indicated by a minus sign. Round intermediate calculations to at least 4 decimal places and final answers to 2 decimal places.)

Confidence interval is_______to_______.

b. Specify the competing hypotheses in order to test whether the mean difference differs from zero.

• H₀: μ_D ≥ 0; H_A: μ_D < 0

• H₀: μ_D = 0; H_A: μ_D ≠ 0

• H₀: μ_D ≤ 0; H_A: μ_D > 0

c. Using the confidence interval from part a, are you able to reject H₀?

• No

• Yes

d. Interpret the results at αα = 0.1.

• We cannot conclude that the mean difference differs from zero.

• We conclude that the mean difference differs from zero.

• We cannot conclude that population mean 2 is greater than population mean 1.

• We conclude that population mean 2 is greater than population mean 1.

Answer 1