# Stats 153

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question
Which of the following is NOT true aboutâ€‹ P-values in hypothesisâ€‹ testing? Choose the correct answer below. A. If the P isâ€‹ high, the null will fly. B. Theâ€‹ P-value separates the critical region from the values that do not lead to rejection of the null hypothesis. C. If the P isâ€‹ low, the null must go. D. Theâ€‹ P-value is an area.
B
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Which of the following is NOT a criterion for making a decision in a hypothesisâ€‹ test? Choose the correct answer below. A. If â€‹P-valueless than or equalsalphaâ€‹, the decision is to reject the null hypothesis.â€‹ Otherwise, we fail to reject the null hypothesis. B. If theâ€‹ P-value is less thanâ€‹ 0.05, the decision is to reject the null hypothesis.â€‹ Otherwise, we fail to reject the null hypothesis. .C. If the test statistic falls within the criticalâ€‹ region, the decision is to reject the null hypothesis. D. If a confidence interval does not include a claimed value of a populationâ€‹ parameter, the decision is to reject the null hypothesis.
B
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Theâ€‹ _________ of a hypothesis test is the probability â€‹(1 - betaâ€‹) of rejecting a false null hypothesis.
POWER
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Which of the following is NOT a requirement of testing a claim about a population proportion using a formal method of hypothesisâ€‹ testing? Choose the correct answer below. A. The conditions for a binomial distribution are satisfied. B. The lowercaseâ€‹ symbol, p, represents the probability of getting a test statistic at least as extreme as the one representing sample data and is needed to test the claim. C. The conditions npgreater than5 and nqgreater than5 are both satisfied. D. The sample observations are a simple random sample.
B
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Which of the following is NOT true of using the binomial probability distribution to test claims about aâ€‹ proportion? Choose the correct answer below. A. In aâ€‹ right-tailed test, theâ€‹ P-value is the probability of getting x or more successes among the n trials. B. One requirement of this method is that npgreater than5 and nqgreater than5. C. In aâ€‹ left-tailed test, theâ€‹ P-value is the probability of getting x or fewer successes among the n trials. D. This method uses the binomial probability distribution with theâ€‹ P-value method and uses the value of p assumed in the null hypothesis.
B
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Which of the following is not true when using the confidence interval method for testing a claim about mu when sigma isâ€‹ unknown? Choose the correct answer below. A. Theâ€‹ P-value method and the classical method are not equivalent to the confidence interval method in that they may yield different results. B. For aâ€‹ one-tailed hypothesis test with a 0.05 significanceâ€‹ level, one must construct aâ€‹ 90% confidence interval. C. Theâ€‹ P-value method, the traditionalâ€‹ method, and the confidence interval method are equivalent and yield the same results. D. For aâ€‹ two-tailed hypothesis test with a 0.05 significanceâ€‹ level, one must construct aâ€‹ 95% confidence interval.
A
question
Which of the following is NOT a requirement for testing a claim about a mean with sigma â€‹known? Choose the correct answer below. A. If the sample resultsâ€‹ (or more extremeâ€‹ results) can easily occur when the null hypothesis isâ€‹ true, we attribute the relatively small discrepancy between the assumption and the sample results to chance. B. A conclusion based on a confidence interval estimate will be the same as a conclusion based on a hypothesis test. C. â€‹If, under a givenâ€‹ assumption, there is an exceptionally small probability of getting sample results at least as extreme as the results that wereâ€‹ obtained, we conclude that the assumption is probably not correct. D. If the sample resultsâ€‹ (or more extremeâ€‹ results) cannot easily occur when the null hypothesis isâ€‹ true, we explain the discrepancy between the assumption and the sample results by concluding that the assumption isâ€‹ true, so we do not reject the assumption.
D
question
Which of the following is not a characteristic of the tâ€‹ test? Choose the correct answer below. A. The Student t distribution is different for different sample sizes. B. The Student t distribution has the same general bell shape as the standard normal distribution. C. The t test is robust against a departure from normality. D. The Student t distribution has a mean of tequals0 and a standard deviation of sequals1.
D
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Which of the following is NOT a requirement for testing a claim about a population mean with sigma â€‹known? Choose the correct answer below. A. Either the population is normally distributed or ngreater than30 or both. B. The value of the population standard deviation is known. C. The sample is a simple random sample. D. The sampleâ€‹ mean, x overbar is greater than 30.
D
question
Which of the following is NOT true of confidence interval estimates of the difference between two populationâ€‹ proportions? Choose the correct answer below. A. A confidence interval is used to test a claim about two population proportions. B. The confidence interval uses a standard deviation based on estimated values of the population proportions. C. A confidence interval is used to estimate the difference between two population proportions. D. If a confidence interval estimate of p 1minusp 2 does not includeâ€‹ 0, we have evidence suggesting that p 1 and p 2 have different values.
A
question
Which of the following is NOT a reason why the procedures to estimate differences of two proportions or testing a claim about two proportionsâ€‹ work? Choose the correct answer below. A. The variance of the differences between two independent random variables is the sum of their individual variances. B. The form of the confidence interval utilizes the same variance as when testing claims using hypothesis tests. C. The pooled estimate of the common value of p 1 and p 2 is p overbarequalsStartFraction x 1 plus x 2 Over n 1 plus n 2 EndFraction . D. Since ModifyingAbove p with caret 1 and ModifyingAbove p with caret 2 are each approximated by a normalâ€‹ distribution, the difference ModifyingAbove p with caret 1minusModifyingAbove p with caret 2 will also be approximated by a normal distribution with mean p 1minusp 2.
B
question
Which of the following is NOT true when dealing with independentâ€‹ samples? Choose the correct answer below. A. The confidence interval estimate of Âµ 1minusÂµ 2 is left parenthesis x overbar 1 minus x overbar 2 right parenthesis minus Upper E less than left parenthesis Âµ 1 minus Âµ 2 right parenthesis less than left parenthesis x overbar 1 minus x overbar 2 right parenthesis plus Upper E. B. When making an inference about the twoâ€‹ means, theâ€‹ P-value and traditional methods of hypothesis testing result in the same conclusion as the confidence interval method. C. The null hypothesis Âµ 1equalsÂµ 2 or Âµ 1 minus Âµ 2 equals 0 can be tested using theâ€‹ P-value method, the traditionalâ€‹ method, or by determining if the confidence interval limits for Âµ 1minusÂµ 2 contain 0. D. The variance of the differences between two independent random variables equals the variance of the first random variable minus the variance of the second random variable.
D
question
a. If s Subscript 1 Superscript 2 represents the larger of two sampleâ€‹ variances, can the F test statistic ever be less thanâ€‹ 1?
NO
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b. Can the F test statistic ever be a negativeâ€‹ number?
â€‹â€‹No, because sample variances cannot beâ€‹ negative, and the result of dividing the squares of two nonnegative numbers is never negative.
question
c. If testing the claim that sigma Subscript 1 Superscript 2 Baseline not equals sigma Subscript 2 Superscript 2â€‹, what do we know about the two samples if the test statistic is Fequalsâ€‹1? A. The two samples have fairly different standard deviationsâ€‹ (or variances). B. The two samples have the same standard deviationâ€‹ (or variance). C. The two samples come from populations with the same standard deviationâ€‹ (or variance). D. The two samples have radically different standard deviationsâ€‹ (or variances).
B
question
The F distribution is:
Skewed Right
question
Which of the following is NOT true of the Fâ€‹ test? Choose the correct answer below. A. This test requires that both populations have normal distributions. B. This test uses the F distribution. C. This test compares two population variances or standard deviations. D. This test is very resistant to departures from normal distributions.
D
question
Which of the following is NOT a requirement for testing a claim about two population standard deviations orâ€‹ variances? Choose the correct answer below. A. This test requires that both populations have normal distributions. B. One of the populations is normally distributed. C. The two samples are simple random samples. D. The populations are independent.
B
question
Which of the following is NOT true of the Fâ€‹ test? Choose the correct answer below. A. The count five method is a relatively simple alternative to the Fâ€‹ test, and it does not require normally distributed populations. B. Allâ€‹ one-tailed F tests will beâ€‹ right-tailed. C. Small values of F are evidence against sigma Subscript 1 Superscript 2 Baseline equals sigma Subscript 2 Superscript 2.