Hypothesis Test for Two Sample Means

The hypotheses are:

H0: μ1 = μ2

H1: μ1 < μ2

The population standard deviations are known.

What test is the most appropriate?

• z test

• independent sample t-test

• chi-square test

• F test

An independent sample t-test is used to test the following hypotheses

H0: μ1 = μ2

H1: μ1 < μ2

Sample 1: size = 15, mean = 20.3, SD =7.4

Sample 2: size = 20, mean = 25.2, SD = 15.6

Variances are assumed to be unequal. Find the critical t value at 0.05 significance level.

• - 1.645

• - 1.761

• - 1.763

• - 1.96

An independent sample t-test is used to test the following hypotheses

H0: μ1 = μ2

H1: μ1 < μ2

Sample 1: size = 15, mean = 20.3, SD =7.4

Sample 2: size = 20, mean = 25.2, SD = 15.6

Variances are assumed to be unequal. Find the test value. (Round the answer to 3 decimal places.)

An independent sample t-test is used to test the following hypotheses

H0: μ1 = μ2

H1: μ1 ≠ μ2

Sample 1: size = 15, mean = 20.3, SD =7.4

Sample 2: size = 20, mean = 25.2, SD = 15.6

Variances are assumed to be unequal. The test value is computed to be -1.232. Find P-value. (Round the answer to 3 decimal places.)

The management of Discount Furniture designed an incentive plan for salespeople. To evaluate this innovative plan, 12 salespeople were selected at random, and their weekly incomes before and after the plan were recorded. Assume the variable is approximately normally distributed. The research question: "Was there a significant increase in the typical salesperson’s weekly income due to the innovative incentive plan?"

What is the conclusion at the 0.05 level of significance?

• There is enough evidence to reject the claim that the typical salesperson's weekly income has increased due to the innovative incentive plan.

• There is not enough evidence to reject the claim that the typical salesperson's weekly income has increased due to the innovative incentive plan.

• There is not enough evidence to support the claim that the typical salesperson's weekly income has increased due to the innovative incentive plan.

• There is enough evidence to support the claim that the typical salesperson's weekly income has increased due to the innovative incentive plan.

The hypotheses are:

H0: μ1 = μ2

H1: μ1 < μ2

The population standard deviations are unknown, samples are independent.

What test is the most appropriate?

• z test

• independent sample t-test

• chi-square test

• F test

An independent sample t-test is used to test the following hypotheses

H0: μ1 = μ2

H1: μ1 > μ2

Sample 1: size = 15, mean = 28.3, SD =7.4

Sample 2: size = 20, mean = 25.2, SD = 9.6

Variances are assumed to be equal. Find the critical t value at 0.05 significance level.

• 1.645

• 1.692

• 1.763

• None of these choices

The hypotheses are:

H0: σ1 = σ2

H1: σ1 < σ2

What test is the most appropriate?

• z test

• independent sample t-test

• chi-square test

• F test