Title: Statistics for Management and Economics s1

Chapter 10 Page 1 of 7 WebQuizzing – Ch. 10 Book ISBN-10 0538477490 Book ISBN-13 9780538477499 Author: Gerald Keller Title: Statistics for Management and Economics Ed: 9e

# Questions Submitted: 20 Multiple Choice

1. The probability of a Type I error is denoted by: A. B. 1- C. D. 1-

Analysis: A. Incorrect. The probability of a Type I error is denoted by B. Incorrect. The probability of a Type I error is denoted by C. Correct. The probability of a Type I error is denoted by D. Incorrect. The probability of a Type I error is denoted by ANSWER: C Ref: Section 10.1

2. A Type I error is committed if we make: A. a correct decision when the null hypothesis is false. B. a correct decision when the null hypothesis is true. C. an incorrect decision when the null hypothesis is false. D. an incorrect decision when the null hypothesis is true.

Analysis: A. Incorrect. A Type I error is committed if we make an incorrect decision when the null hypothesis is true. B. Incorrect. A Type I error is committed if we make an incorrect decision when the null hypothesis is true. C. Incorrect. A Type I error is committed if we make an incorrect decision when the null hypothesis is true. D. Correct. A Type I error is committed if we make an incorrect decision when the null hypothesis is true. ANSWER: D Ref: Section 10.1

3. A Type II error is committed if we make: A. a correct decision when the null hypothesis is false. B. a correct decision when the null hypothesis is true. C. an incorrect decision when the null hypothesis is false. D. an incorrect decision when the null hypothesis is true.

Analysis: Chapter 10 Page 2 of 7 A. Incorrect. A Type II error is committed if we make an incorrect decision when the null hypothesis is false. B. Incorrect. A Type II error is committed if we make an incorrect decision when the null hypothesis is false. C. Correct. A Type II error is committed if we make an incorrect decision when the null hypothesis is false. D. Incorrect. A Type II error is committed if we make an incorrect decision when the null hypothesis is false. ANSWER: C Ref: Section 10.1

4. The hypothesis of most interest to the researcher is: A. the alternative hypothesis. B. the null hypothesis. C. both hypotheses are of equal interest. D. Neither hypothesis is of interest.

Analysis: A. Correct. The hypothesis of most interest to the researcher is the alternative hypothesis. B. Incorrect. The hypothesis of most interest to the researcher is the alternative hypothesis. C. Incorrect. The hypothesis of most interest to the researcher is the alternative hypothesis. D. Incorrect. The hypothesis of most interest to the researcher is the alternative hypothesis. ANSWER: A Ref: Section 10.1

5. The level of significance can be: A. any number between –1.0 and 1.0. B. any number greater than zero. C. any number greater than 1.96 or less than -1.96. D. None of the above.

Analysis: A. Incorrect. None of the above. B. Incorrect. None of the above. C. Incorrect. None of the above. D. Correct. None of the above. ANSWER: D Ref: Section 10.1

6. Which of the following is an appropriate null hypothesis? A. The proportion of a population is equal to 60. B. The proportion of a sample is equal to 60. C. The proportion of a population is not equal to 60. D. All of these choices are true.

Analysis: A. Correct. The proportion of a population is equal to 60 is an appropriate null hypothesis. Chapter 10 Page 3 of 7 B. Incorrect. The proportion of a population is equal to 60 is an appropriate null hypothesis. C. Incorrect. The proportion of a population is equal to 60 is an appropriate null hypothesis. D. Incorrect. The proportion of a population is equal to 60 is an appropriate null hypothesis. ANSWER: A Ref: Section 10.1

7. Which of the following statements is not true? A. The probability of making a Type II error increases as the probability of making a Type I error decreases. B. The probability of making a Type II error and the level of significance are the same. C. The power of the test decreases as the level of significance decreases. D. All of these choices are true.

Analysis: A. Incorrect. The probability of making a Type II error and the level of significance are the same is not true. B. Correct. The probability of making a Type II error and the level of significance are the same is not true. C. Incorrect. The probability of making a Type II error and the level of significance are the same is not true. D. Incorrect. The probability of making a Type II error and the level of significance are the same is not true. ANSWER: B Ref: Section 10.1

8. Which of the following would be an appropriate alternative hypothesis? A. The proportion of a population is equal to 70. B. The proportion of a sample is equal to 70. C. The proportion of a population is greater than 70. D. The proportion of a sample is greater than 70.

Analysis: A. Incorrect. The proportion of a population is greater than 70 is an appropriate alternative hypothesis. B. Incorrect. The proportion of a population is greater than 70 is an appropriate alternative hypothesis. C. Correct. The proportion of a population is greater than 70 is an appropriate alternative hypothesis. D. Incorrect. The proportion of a population is greater than 70 is an appropriate alternative hypothesis. ANSWER: C Ref: Section 10.1

9. If we reject the null hypothesis when it is false, then we have committed: A. a Type II error. B. a Type I error. C. both a Type I error and a Type II error. D. neither a Type I error nor a Type II error. Chapter 10 Page 4 of 7

Analysis: A. Incorrect. Neither a Type I error nor a Type II error. B. Incorrect. Neither a Type I error nor a Type II error. C. Incorrect. Neither a Type I error nor a Type II error. D. Correct. Neither a Type I error nor a Type II error. ANSWER: D Ref: Section 10.3

10. In order to determine the p-value, which of the following is not needed? A. The level of significance. B. Whether the test is one-tail or two-tail. C. The value of the test statistic. D. All of these choices are true.

Analysis: A. Correct. In order to determine the p-value the level of significance is not needed. B. Incorrect. In order to determine the p-value the level of significance is not needed. C. Incorrect. In order to determine the p-value the level of significance is not needed. D. Incorrect. In order to determine the p-value the level of significance is not needed. ANSWER: A Ref: Section 10.2

11. The critical values or are the boundary values for: A. the rejection region(s). B. the level of significance. C. Type I error. D. Type II error.

Analysis: A. Correct. The critical values or are the boundary values for the rejection region(s). B. Incorrect. The critical values or are the boundary values for the rejection region(s). C. Incorrect. The critical values or are the boundary values for the rejection region(s). D. Incorrect. The critical values or are the boundary values for the rejection region(s). ANSWER: A Ref: Section 10.2

12. In a two-tail test for the population proportion, if the null hypothesis is rejected when the alternative hypothesis is true: A. a Type I error is committed. B. a Type II error is committed. C. a correct decision is made. D. a one-tail test should be used instead of a two-tail test.

Analysis: Chapter 10 Page 5 of 7 A. Incorrect. If the null hypothesis is rejected when the alternative hypothesis is true a correct decision is made. B. Incorrect. If the null hypothesis is rejected when the alternative hypothesis is true a correct decision is made. C. Correct. If the null hypothesis is rejected when the alternative hypothesis is true a correct decision is made. D. Incorrect. If the null hypothesis is rejected when the alternative hypothesis is true a correct decision is made. ANSWER: C Ref: Section 10.2

13. Using a confidence interval when conducting a two-tail test for p , we do not reject H if the o hypothesized value for p: A. is to the left of the lower confidence limit (LCL). B. is to the right of the upper confidence limit (UCL). C. falls between the LCL and UCL. D. falls in the rejection region.

Analysis: A. Incorrect. We do not reject Ho if the hypothesized value for p falls between the LCL and UCL. B. Incorrect. We do not reject H if the hypothesized value for p falls between the LCL and UCL. o C. Correct. We do not reject Ho if the hypothesized value for p falls between the LCL and UCL. D. Incorrect. We do not reject Ho if the hypothesized value for p falls between the LCL and UCL. ANSWER: C Ref: Section 10.2

14. If we reject the null hypothesis, we conclude that: A. there is enough statistical evidence to infer that the alternative hypothesis is true. B. there is not enough statistical evidence to infer that the alternative hypothesis is true. C. there is enough statistical evidence to infer that the null hypothesis is true. D. there is not enough statistical evidence to infer that the null hypothesis is true.

Analysis: A. Correct. If we reject the null hypothesis, we conclude that there is enough statistical evidence to infer that the alternative hypothesis is true. B. Incorrect. If we reject the null hypothesis, we conclude that there is enough statistical evidence to infer that the alternative hypothesis is true. C. Incorrect. If we reject the null hypothesis, we conclude that there is enough statistical evidence to infer that the alternative hypothesis is true. D. Incorrect. If we reject the null hypothesis, we conclude that there is enough statistical evidence to infer that the alternative hypothesis is true. ANSWER: A Ref: Section 10.1

15. The p-value criterion for hypothesis testing is to reject the null hypothesis if: A. p-value = Chapter 10 Page 6 of 7 B. p-value < C. p-value > D. - < p-value <

Analysis: A. Incorrect. The p-value criterion for hypothesis testing is to reject the null hypothesis if p-value < B. Correct. The p-value criterion for hypothesis testing is to reject the null hypothesis if p-value < C. Incorrect. The p-value criterion for hypothesis testing is to reject the null hypothesis if p-value < D. Incorrect. The p-value criterion for hypothesis testing is to reject the null hypothesis if p-value < ANSWER: B Ref: Section 10.2

16. The p-value is a probability that measures the support (or lack of support) for the

A. Null Hypothesis B. Alternate Hypothesis C. Null or Alternate Hypothesis D. The sample proportion

Analysis: A. Correct. The p-value is a probability that measures the support (or lack of support) for the Null Hypothesis. B. Incorrect. The p-value is a probability that measures the support (or lack of support) for the Null Hypothesis. C. Incorrect. The p-value is a probability that measures the support (or lack of support) for the Null Hypothesis. D. Incorrect. The p-value is a probability that measures the support (or lack of support) for the Null Hypothesis. ANSWER: A Ref: Section 10.3

17. The power of a test is measured by its capability of: A. rejecting a null hypothesis that is true. B. not rejecting a null hypothesis that is true. C. rejecting a null hypothesis that is false. D. not rejecting a null hypothesis that is false.

Analysis: A. Incorrect. The power of a test is measured by its capability of rejecting a null hypothesis that is false. B. Incorrect. The power of a test is measured by its capability of rejecting a null hypothesis that is false. C. Correct. The power of a test is measured by its capability of rejecting a null hypothesis that is false. D. Incorrect. The power of a test is measured by its capability of rejecting a null hypothesis that is false. Chapter 10 Page 7 of 7 ANSWER: C Ref: Section 10.3

18. The power of a test is denoted by: A. B. C. 1- D. 1-

Analysis: A. Incorrect. The power of a test is denoted by1- B. Incorrect. The power of a test is denoted by1- C. Incorrect. The power of a test is denoted by1- D. Correct. The power of a test is denoted by1- ANSWER: D Ref: Section 10.3

19. For a given sample size n, if the level of significanceis decreased, the power of the test will: A. increase. B. decrease. C. remain the same. D. Not enough information to tell.

Analysis: A. Incorrect. The power of the test will decrease. B. Correct. The power of the test will decrease. C. Incorrect. The power of the test will decrease. D. Incorrect. The power of the test will decrease. ANSWER: B Ref: Section 10.3

20. Determining which statistical test to use in an analysis of data is based upon which two factors? A. The sample size and the purpose of the statistical inference B. The type of data and the purpose of the statistical inference. C. The sample size and the type of data. D. None of these choices.

Analysis: A. Incorrect. The type of data and the purpose of the statistical inference. B. Correct. The type of data and the purpose of the statistical inference. C. Incorrect. The type of data and the purpose of the statistical inference. D. Incorrect. The type of data and the purpose of the statistical inference.

ANSWER: B Ref: Section 10.4