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

A)

H0: > 0.10 versus Ha: ≤ 0.10.

B)

H0: ≤ 0.10 versus Ha: > 0.10.

C)

H0: > 0.10 versus Ha: < 0.10.




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.

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

A)

H0: μ < 0.05 versus Ha: μ ≥ 0.05.

B)

H0: μ < 0.05 versus Ha: μ > 0.05.

C)

H0: μ ≥ 0.05 versus Ha: μ < 0.05.




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.

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James Ambercrombie believes that the average return on equity in the utility industry, μ, is greater than 10%. What is null (H0) and alternative (Ha) hypothesis for his study?

A)
H0: μ = 0.10 versus Ha: μ ≠ 0.10.
B)
H0: μ ≥ 0.10 versus Ha: μ < 0.10.
C)
H0: μ ≤ 0.10 versus Ha: μ > 0.10.



This is a one-sided alternative because of the “greater than” belief. We expect to reject the null.

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Robert Patterson, an options trader, believes that the return on options trading is higher on Mondays than on other days. In order to test his theory, he formulates a null hypothesis. Which of the following would be an appropriate null hypothesis? Returns on Mondays are:

A)
not greater than returns on other days.
B)
greater than returns on other days.
C)
less than returns on other days.



An appropriate null hypothesis is one that the researcher wants to reject. If Patterson believes that the returns on Mondays are greater than on other days, he would like to reject the hypothesis that the opposite is true–that returns on Mondays are not greater than returns on other days.

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A researcher is testing the hypothesis that a population mean is equal to zero. From a sample with 64 observations, the researcher calculates a sample mean of -2.5 and a sample standard deviation of 8.0. At which levels of significance should the researcher reject the hypothesis?

1% significance

5% significance

10% significance

A)

Fail to reject

Fail to reject

Reject

B)

Fail to reject

Reject

Reject

C)

Reject

Fail to reject

Fail to reject



This is a two-tailed test. With a sample size greater than 30, using a z-test is acceptable. The test statistic = = ?2.5. For a two-tailed z-test, the critical values are ±1.645 for a 10% significance level, ±1.96 for a 5% significance level, and ±2.58 for a 1% significance level. The researcher should reject the hypothesis at the 10% and 5% significance levels, but fail to reject the hypothesis at the 1% significance level.

Using Student's t-distribution, the critical values for 60 degrees of freedom (the closest available in a typical table) are ±1.671 for a 10% significance level, ±2.00 for a 5% significance level, and ±2.66 for a 1% significance level. The researcher should reject the hypothesis at the 10% and 5% significance levels, but fail to reject the hypothesis at the 1% significance level.

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Which one of the following is the most appropriate set of hypotheses to use when a researcher is trying to demonstrate that a return is greater than the risk-free rate? The null hypothesis is framed as a:

A)
less than statement and the alternative hypothesis is framed as a greater than or equal to statement.
B)
greater than statement and the alternative hypothesis is framed as a less than or equal to statement.
C)
less than or equal to statement and the alternative hypothesis is framed as a greater than statement.



If a researcher is trying to show that a return is greater than the risk-free rate then this should be the alternative hypothesis. The null hypothesis would then take the form of a less than or equal to statement.

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Which one of the following best characterizes the alternative hypothesis? The alternative hypothesis is usually the:

A)
hypothesis to be proved through statistical testing.
B)
hypothesis that is accepted after a statistical test is conducted.
C)
hoped-for outcome.



The alternative hypothesis is typically the hypothesis that a researcher hopes to support after a statistical test is carried out. We can reject or fail to reject the null, not 'prove' a hypothesis.

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What is the most common formulation of null and alternative hypotheses?

A)
Less than for the null and greater than for the alternative.
B)
Equal to for the null and not equal to for the alternative.
C)
Greater than or equal to for the null and less than for the alternative.



The most common set of hypotheses will take the form of an equal to statement for the null and a not equal to statement for the alternative.

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Jill Woodall believes that the average return on equity in the retail industry, μ, is less than 15%. What is null (H0) and alternative (Ha) hypothesis for her study?

A)
H0: μ < 0.15 versus Ha: μ = 0.15.
B)
H0: μ ≥ 0.15 versus Ha: μ < 0.15.
C)
H0: μ = 0.15 versus Ha: μ ≠ 0.15.



This is a one-sided alternative because of the “less than” belief. We expect to reject the null.

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An analyst is testing to see if the mean of a population is less than 133. A random sample of 50 observations had a mean of 130. Assume a standard deviation of 5. The test is to be made at the 1% level of significance.

z

0.00

0.01

0.02

0.03

0.04

0.05

0.06

0.0

0.0000

0.0040

0.0080

0.0120

0.0160

0.0199

0.0239

0.1

0.0398

0.0438

0.0478

0.0517

0.0557

0.0596

0.0636

0.2

0.0793

0.0832

0.0871

0.0910

0.0948

0.0987

0.1026

0.3

0.1179

0.1217

0.1255

0.1293

0.1331

0.1368

0.1406

|

|

|

|

|

|

|

|

1.7

0.4554

0.4564

0.4573

0.4582

0.4591

0.4599

0.4608

1.8

0.4641

0.4649

0.4656

0.4664

0.4671

0.4678

0.4686

1.9

0.4713

0.4719

0.4726

0.4732

0.4738

0.4744

0.4750

2.0

0.4772

0.4778

0.4783

0.4788

0.4793

0.4798

0.4803

2.1

0.4821

0.4826

0.4830

0.4834

0.4838

0.4842

0.4846

2.2

0.4861

0.4864

0.4868

0.4871

0.4875

0.4878

0.4881

2.3

0.4893

0.4896

0.4898

0.4901

0.4904

0.4906

0.4909

2.4

0.4918

0.4920

0.4922

0.4925

0.4927

0.4929

0.4931

The null hypothesis is:

A)
μ ≤ 133.
B)
μ > 133.
C)
μ ≥ 133.



The null hypothesis is the hypothesis that the researcher wants to reject. Here the hypothesis that is being looked for is that the mean of a population is less than 133. The null hypothesis is that the mean is greater than or equal to 133. The question is whether the null hypothesis will be rejected in favor of the alternative hypothesis that the mean is less than 133.


The calculated test statistic is:

A)
+1.33.
B)
-1.33.
C)
-4.24.



A test statistic is calculated by subtracting the hypothesized parameter from the parameter that has been estimated and dividing the difference by the standard error of the sample statistic. Here, the test statistic = (sample mean – hypothesized mean) / ((sample standard deviation / (sample size)1/2)) = (130 – 133) / (5 / 501/2) = (-3) / (5 / 7.0711) = -4.24.


The critical value is:

A)
2.47.
B)
-2.38.
C)
-2.33.



This is a one-tailed test with a significance level of 0.01. The critical value for a one-tailed test at a 1% level of significance is -2.33.


You should:

A)
reject the null hypothesis.
B)
reject the alternative hypothesis.
C)
accept the null hypothesis.



The calculated test statistic of -4.24 falls to the left of the z-statistic of -2.33, and is in the rejection region. Thus, the null hypothesis is rejected and the conclusion is that the population mean is less than 133.

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