ISDS terms
For a given level of significance (α), if the sample size n is increased, the probability of a Type II error (β) A) will decrease. B) will increase. C) will remain the same. D) cannot be determined.
will decrease.
For a given sample size n, if the level of significance (α) is decreased, the power of the test A) will increase. B) will decrease. C) will remain the same. D) cannot be determined.
will decrease.
A Type II error is committed when
you don't reject a null hypothesis that is false
A Type I error is committed when
you reject a null hypothesis that is true
The symbol for the probability of committing a Type I error of a statistical test is A) α. B) 1 - α. C) β. D) 1 - β.
α.
The symbol for the probability of committing a Type II error of a statistical test is A) α. B) 1 - α. C) β. D) 1 - β.
β.
The symbol for the power of a statistical test is A) α. B) 1 - α. C) β. D) 1 - β.
1 - β.
True or False: The statement of the null hypothesis always contains an equality.
true
True or False: In instances in which there is insufficient evidence to reject the null hypothesis, you must make it clear that this has proven that the null hypothesis is true.
false
True or False: Suppose, in testing a hypothesis about a mean, the Z test statistic is computed to be 2.04. The null hypothesis should be rejected if the chosen level of significance is 0.01 and a two-tail test is used.
false
True or False: The larger the p-value, the more likely you are to reject the null hypothesis.
false
If, as a result of a hypothesis test, you reject the null hypothesis when it is false, then you have committed A) a Type II error. B) a Type I error. C) no error. D) an acceptance error.
no error.
The power of a test is measured by its capability of
rejecting a null hypothesis that is false
The symbol for the confidence coefficient of a statistical test is A) α. B) 1 - α. C) β. D) 1 - β.
1 - α.
Which of the following statements is not true about the level of significance in a hypothesis test? A) The larger the level of significance, the more likely you are to reject the null hypothesis. B) The level of significance is the maximum risk we are willing to accept in making a Type I error. C) The significance level is also called the α level. D) The significance level is another name for Type II error.
The significance level is another name for Type II error.
True or False: Suppose, in testing a hypothesis about a mean, the p-value is computed to be 0.043. The null hypothesis should be rejected if the chosen level of significance is 0.05.
True
True or False: "What conclusions and interpretations can you reach from the results of the hypothesis test?" is not an important question to ask when performing a hypothesis test.
false
If a researcher rejects a true null hypothesis, she has made a(n) ________ error.
Type I
If a researcher does not reject a false null hypothesis, she has made a(n) ________ error.
Type II
True or False: In a hypothesis test, it is irrelevant whether the test is a one-tail or two-tail test.
false
True or False: Suppose, in testing a hypothesis about a mean, the p-value is computed to be 0.034. The null hypothesis should be rejected if the chosen level of significance is 0.01.
false
If the Type I error (α) for a given test is to be decreased, then for a fixed sample size n, A) the Type II error (β) will also decrease. B) the Type II error (β) will increase. C) the power of the test will increase. D) a one-tail test must be utilized.
the Type II error (β) will increase.
The symbol for the level of significance of a statistical test is A) α. B) 1 - α. C) β. D) 1 - β.
α.
Suppose we wish to test H0 : μ ≤ 47 versus H1 : μ > 47. What will result if we conclude that the mean is greater than 47 when its true value is really 52? A) We have made a Type I error. B) We have made a Type II error. C) We have made a correct decision. D) None of the above are correct.
We have made a correct decision.
If a researcher does not reject a true null hypothesis, she has made a(n) ________ decision.
correct
A ________ is a numerical quantity computed from the data of a sample and is used in reaching a decision on whether or not to reject the null hypothesis. A) significance level B) critical value C) test statistic D) parameter
critical value
The value that separates a rejection region from a non-rejection region is called the ________.
critical value
True or False: You should report only the results of hypothesis tests that show statistical significance and omit those for which there is insufficient evidence in the findings.
false
If a test of hypothesis has a Type I error probability (α) of 0.01, it means that A) if the null hypothesis is true, you don't reject it 1% of the time. B) if the null hypothesis is true, you reject it 1% of the time. C) if the null hypothesis is false, you don't reject it 1% of the time. D) if the null hypothesis is false, you reject it 1% of the time.
if the null hypothesis is true, you reject it 1% of the time.
Which of the following would be an appropriate null hypothesis?
the mean of the population is equal to 55 the population proportion is not less than .65
Which of the following would be an appropriate alternative hypothesis?
the mean of the population is greater than 55 the population proportion is less than .65
If the p-value is less than α in a two-tail test,
the null hypothesis should be rejected.
The power of a statistical test is A) the probability of not rejecting H0 when it is false. B) the probability of rejecting H0 when it is true. C) the probability of not rejecting H0 when it is true. D) the probability of rejecting H0 when it is false.
the probability of rejecting H0 when it is false.
True or False: "Is the intended sample size large enough to achieve the desired power of the test for the level of significance chosen?" should be among the questions asked when performing a hypothesis test.
true
True or False: In conducting research, you should document both good and bad results.
true
True or False: In instances in which there is insufficient evidence to reject the null hypothesis, you must make it clear that this does not prove that the null hypothesis is true.
true
True or False: In testing a hypothesis, you should always raise the question concerning the purpose of the study, survey or experiment.
true
True or False: The smaller the p-value, the stronger the evidence is against the null hypothesis.
true
True or False: The test statistic measures how close the computed sample statistic has come to the hypothesized population parameter.
true
If you know that the level of significance (α) of a test is 5%, you can tell that the probability of committing a Type II error (β) is A) 2.5%. B) 95%. C) 97.5%. D) unknown.
unknown.
If an economist wishes to determine whether there is evidence that mean family income in a community exceeds $50,000, A) either a one-tail or two-tail test could be used with equivalent results. B) a one-tail test should be utilized. C) a two-tail test should be utilized. D) None of the above.
a one-tail test should be utilized.
It is possible to directly compare the results of a confidence interval estimate to the results obtained by testing a null hypothesis if A) a two-tail test for μ is used. B) a one-tail test for μ is used. C) Both of the previous statements are true. D) None of the previous statements is true.
a two-tail test for μ is used.
If an economist wishes to determine whether there is evidence that mean family income in a community equals $50,000, A) either a one-tail or two-tail test could be used with equivalent results. B) a one-tail test should be utilized. C) a two-tail test should be utilized. D) None of the above.
a two-tail test should be utilized.
If you know that the probability of committing a Type II error (β) is 5%, you can tell that the power of the test is A) 2.5%. B) 95%. C) 97.5%. D) unknown.
95%.
If a researcher rejects a false null hypothesis, she has made a(n) ________ decision.
correct
True or False: A proper methodology in performing hypothesis tests is to ask whether a random sample can be selected from the population of interest.
true