6.Jill Woodall believes that the average return on equity in the retail industry, µ, is less than 15 percent. What are the null (H₀) and alternative (H_a) hypotheses for her study?

A)   H₀: µ ≥ 0.15 versus H_a: µ < 0.15.

B)   H₀: µ < 0.15 versus H_a: µ ≥ 0.15.

C)   H₀: µ ≤ 0.15 versus H_a: µ > 0.15.

D)   H₀: µ > 0.15 versus H_a: µ < 0.15.

7.Brian Ci believes that the average return on equity in the airline industry, µ, is less than 5 percent. What are the appropriate null (H₀) and alternative (H_a) hypotheses to test this belief?

A)   H₀: µ ≥ 0.05 versus H_a: µ < 0.05.

B)   H₀: µ < 0.05 versus H_a: µ > 0.05.

C)   H₀: µ > 0.05 versus H_a: µ < 0.05.

D)   H₀: µ < 0.05 versus H_a: µ ≥ 0.05.

8.George Appleton believes that the average return on equity in the amusement industry, µ, is greater than 10 percent. What is the null (H₀) and alternative (H_a) hypothesis for his study?

A)   H₀: > 0.10 versus H_a: < 0.10.

B)   H₀: < 0.10 versus H_a: > 0.10.

C)   H₀: > 0.10 versus H_a: ≤ 0.10.

D)   H₀: ≤ 0.10 versus H_a: > 0.10.

9.James Ambercrombie believes that the average return on equity in the utility industry, µ, is greater than 10 percent. What are the null (H₀) and alternative (H_a) hypotheses for his study?

A)   H₀: µ > 0.10 versus H_a: µ < 0.10.

B)   H₀: µ ≤ 0.10 versus H_a: µ > 0.10.

C)   H₀: µ < 0.10 versus H_a: µ > 0.10.

D)   H₀: µ < 0.10 versus H_a: µ ≥ 0.10.

答案和详解如下：

6.Jill Woodall believes that the average return on equity in the retail industry, µ, is less than 15 percent. What are the null (H₀) and alternative (H_a) hypotheses for her study?

A)   H₀: µ ≥ 0.15 versus H_a: µ < 0.15.

B)   H₀: µ < 0.15 versus H_a: µ ≥ 0.15.

C)   H₀: µ ≤ 0.15 versus H_a: µ > 0.15.

D)   H₀: µ > 0.15 versus H_a: µ < 0.15.

The correct answer was A)

This is a one-sided alternative because of the "less than" belief.

7.Brian Ci believes that the average return on equity in the airline industry, µ, is less than 5 percent. What are the appropriate null (H₀) and alternative (H_a) hypotheses to test this belief?

A)   H₀: µ ≥ 0.05 versus H_a: µ < 0.05.

B)   H₀: µ < 0.05 versus H_a: µ > 0.05.

C)   H₀: µ > 0.05 versus H_a: µ < 0.05.

D)   H₀: µ < 0.05 versus H_a: µ ≥ 0.05.

The correct answer was A)

The alternative hypothesis is determined by the theory or the belief. The researcher specifies the null as the hypothesis that he wishes to reject (in favor of the alternative). Note that this is a one-sided alternative because of the "less than" belief.

8.George Appleton believes that the average return on equity in the amusement industry, µ, is greater than 10 percent. What is the null (H₀) and alternative (H_a) hypothesis for his study?

A)   H₀: > 0.10 versus H_a: < 0.10.

B)   H₀: < 0.10 versus H_a: > 0.10.

C)   H₀: > 0.10 versus H_a: ≤ 0.10.

D)   H₀: ≤ 0.10 versus H_a: > 0.10.

The correct answer was D)

The alternative hypothesis is determined by the theory or the belief. The researcher specifies the null as the hypothesis that he wishes to reject (in favor of the alternative). Note that this is a one-sided alternative because of the "greater than" belief.

9.James Ambercrombie believes that the average return on equity in the utility industry, µ, is greater than 10 percent. What are the null (H₀) and alternative (H_a) hypotheses for his study?

A)   H₀: µ > 0.10 versus H_a: µ < 0.10.

B)   H₀: µ ≤ 0.10 versus H_a: µ > 0.10.

C)   H₀: µ < 0.10 versus H_a: µ > 0.10.

D)   H₀: µ < 0.10 versus H_a: µ ≥ 0.10.

The correct answer was B)

This is a one-sided alternative because of the "greater than" belief.