Deck 12: Testing Hypotheses About Proportions

Question 1

Use the following information for questions:
For each statement, determine if the statement is a typical null hypothesis $H_0$ or alternative hypothesis $H_a$ .

-There is no difference between the proportion of overweight men and overweight women in America.

A) Null hypothesis
B) Alternative hypothesis

Answer 1

Null hypothesis

Question 2

Use the following information for questions:
For each statement, determine if the statement is a typical null hypothesis $H_0$ or alternative hypothesis $H_a$ .

-The proportion of overweight men is greater than the proportion of overweight women in America.

A) Null hypothesis
B) Alternative hypothesis

Answer 2

Alternative hypothesis

Question 3

Use the following information for questions:
For each statement, determine if the statement is a typical null hypothesis $H_0$ or alternative hypothesis $H_a$ .

-The average time to graduate for undergraduate English majors is less than the average time to graduate for undergraduate history majors.

A) Null hypothesis
B) Alternative hypothesis

Answer 3

Alternative hypothesis

Question 4

Use the following information for questions:
For each statement, determine if the statement is a typical null hypothesis $H_0$ or alternative hypothesis $H_a$ .

-The average price of a particular statistics textbook over the internet is the same as the average price of the textbook sold at all bookstores in a college town.

A) Null hypothesis
B) Alternative hypothesis

Question 5

Use the following information for questions:
For each statement, determine if the statement is a typical null hypothesis $H_0$ or alternative hypothesis $H_a$ .

-The graduation rate for all division I athletes is not equal to the 85% claimed by the NCAA.

A) Null hypothesis
B) Alternative hypothesis

Question 6

Use the following information for questions:
For each statement, determine if the statement is a typical null hypothesis $H_0$ or alternative hypothesis $H_a$ .

-The proportion of second year college students who live in a dormitory has decreased from the proportion in 1999, which was known to be 25%.

A) Null hypothesis
B) Alternative hypothesis

Question 7

A two-sided or two-tailed hypothesis test is one in which

A) the null hypothesis includes values in either direction from a specific standard.
B) the null hypothesis includes values in one direction from a specific standard.
C) the alternative hypothesis includes values in one direction from a specific standard
D) the alternative hypothesis includes values in either direction from a specific standard

Question 8

Null and alternative hypotheses are statements about

A) population parameters.
B) sample parameters.
C) sample statistics.
D) it depends - sometimes population parameters and sometimes sample statistics.

Question 9

Which statement is correct about a p-value?

A) The smaller the p-value the stronger the evidence in favor of the alternative hypothesis.
B) The smaller the p-value the stronger the evidence in favor the null hypothesis
C) Whether a small p-value provides evidence in favor of the null hypothesis depends on whether the test is one-sided or two-sided.
D) Whether a small p-value provides evidence in favor of the alternative hypothesis depends on whether the test is one-sided or two-sided.

Question 10

A hypothesis test gives a p-value of 0.03. If the significance level $\alpha$ = 0.05, the results are said to be

A) not statistically significant because the p-value $\leq$$\alpha$
B) statistically significant because the p-value $\leq$$\alpha$ .
C) practically significant because the p-value $\leq$$\alpha$ .
D) not practically significant because the p-value $\leq$$\alpha$ .

Question 11

A hypothesis test gives a p-value of 0.050. If the significance level $\alpha$ = 0.05, the results are said to be

A) not statistically significant because the p-value is not smaller than $\alpha$ .
B) statistically significant because the p-value $\leq$$\alpha$ .
C) practically significant because the p-value is the same as $\alpha$ .
D) inconclusive because the p-value is not smaller nor larger than $\alpha$ .

Question 12

The likelihood that a statistic would be as extreme or more extreme than what was observed is called a

A) statistically significant result.
B) test statistic.
C) significance level.
D) p-value.

Question 13

The data summary used to decide between the null hypothesis and the alternative hypothesis is called a

A) statistically significant result.
B) test statistic.
C) significance level.
D) p-value.

Question 14

The designated level (typically set at 0.05) to which the p-value is compared to, in order to decide whether the alternative hypothesis is accepted or not is called a

A) statistically significant result.
B) test statistic.
C) significance level.
D) none of the above.

Question 15

When the p-value is less than or equal to the designated level of 0.05, the result is called a

A) statistically significant result.
B) test statistic.
C) significance level.
D) none of the above.

Question 16

Which of the following conclusions is not equivalent to rejecting the null hypothesis?

A) The results are statistically significant.
B) The results are not statistically significant.
C) The alternative hypothesis is accepted.
D) The p-value $\leq$$\alpha$ (the significance level)

Question 17

If the result of a hypothesis test for a proportion is statistically significant, then

A) the null hypothesis is rejected.
B) the alternative hypothesis is rejected.
C) the population proportion must equal the null value.
D) None of the above.

Question 18

The smaller the p-value, the

A) stronger the evidence against the alternative hypothesis.
B) stronger the evidence for the null hypothesis.
C) stronger the evidence against the null hypothesis.
D) None of the above.

Question 19

Which of the following is not a valid conclusion for a hypothesis test?

A) Reject the null hypothesis.
B) Do not reject the null hypothesis.
C) We have proven the null hypothesis is true.
D) We have proven the alternative hypothesis is true.

Question 20

In hypothesis testing for one proportion, the "null value"is used in which of the following?

A) The null hypothesis.
B) The alternative hypothesis.
C) The computation of the test statistic.
D) All of the above.

Question 21

A result is called statistically significant whenever

A) the null hypothesis is true.
B) the alternative hypothesis is true.
C) the p-value is less than or equal to the significance level.
D) the p-value is larger than the significance level.

Question 22

Which one of the following is not true about hypothesis tests?

A) Hypothesis tests are only valid when the sample is representative of the population for the question of interest.
B) Hypotheses are statements about the population represented by the samples.
C) Hypotheses are statements about the sample (or samples) from the population.
D) Conclusions are statements about the population represented by the samples.

Question 23

In a hypothesis test which of the following can (and should) be determined before collecting data?

A) The null and alternative hypotheses.
B) The value of the test statistic.
C) The p-value.
D) Whether the test statistic will be positive or negative.

Question 24

The level of significance (usually .05) associated with a significance test is the probability

A) that the null hypothesis is true.
B) that the alternative hypothesis is true.
C) of not rejecting a true null hypothesis.
D) of rejecting a true null hypothesis.

Question 25

Use the following information for questions:
Suppose the significance level for a hypothesis test is $\alpha$ = 0.05.

-If the p-value is 0.001, the conclusion is to

A) reject the null hypothesis.
B) accept the null hypothesis.
C) not reject the null hypothesis.
D) None of the above.

Question 26

Use the following information for questions:
Suppose the significance level for a hypothesis test is $\alpha$ = 0.05.

-If the p-value is 0.049, the conclusion is to

A) reject the null hypothesis.
B) accept the null hypothesis.
C) not reject the null hypothesis.
D) None of the above.

Question 27

Use the following information for questions:
Suppose the significance level for a hypothesis test is $\alpha$ = 0.05.

-If the p-value is 0.05, the conclusion is to

A) reject the null hypothesis.
B) accept the alternative hypothesis.
C) not reject the null hypothesis.
D) None of the above.

Question 28

Use the following information for questions:
Suppose the significance level for a hypothesis test is $\alpha$ = 0.05.

-If the p-value is 0.999, the conclusion is to

A) reject the null hypothesis.
B) accept the alternative hypothesis.
C) not reject the null hypothesis.
D) None of the above.

Question 29

In hypothesis testing, a Type 1 error occurs when

A) the null hypothesis is not rejected when the null hypothesis is true.
B) the null hypothesis is rejected when the null hypothesis is true.
C) the null hypothesis is not rejected when the alternative hypothesis is true.
D) the null hypothesis is rejected when the alternative hypothesis is true.

Question 30

In hypothesis testing, a Type 2 error occurs when

A) the null hypothesis is not rejected when the null hypothesis is true.
B) the null hypothesis is rejected when the null hypothesis is true.
C) the null hypothesis is not rejected when the alternative hypothesis is true.
D) the null hypothesis is rejected when the alternative hypothesis is true.

Question 31

In a hypothesis test the decision was made to not reject the null hypothesis. Which type of mistake could have been made?

A) Type 1.
B) Type 2.
C) Type 1 if it's a one-sided test and Type 2 if it's a two-sided test.
D) Type 2 if it's a one-sided test and Type 1 if it's a two-sided test.

Question 32

If, in a hypothesis test, the null hypothesis is actually true, which type of mistake can be made?

A) Type 1.
B) Type 2.
C) Type 1 if it's a one-sided test and Type 2 if it's a two-sided test.
D) Type 2 if it's a one-sided test and Type 1 if it's a two-sided test.

Question 33

In an American criminal trial, the null hypothesis is that the defendant is innocent and the alternative hypothesis is that the defendant is guilty. Which of the following describes a Type 2 error for a criminal trial?

A) A guilty verdict for a person who is innocent.
B) A guilty verdict for a person who is not innocent.
C) A not guilty verdict for a person who is guilty
D) A not guilty verdict for a person who is innocent

Question 34

Explain what the statement of the null hypothesis represents in hypothesis testing. Give an example.

Question 35

Explain what the statement of the alternative hypothesis represents in hypothesis testing. Give an example.

Question 36

Explain what is meant by the power of a hypothesis test and suggest one way a researcher might change their study design to increase the power of the test.

Question 37

A drug shows promise as a new treatment for hay fever. The hypotheses below were tested for p = proportion of patients taking this drug who are cured of hay fever.
H₀: p ≤ 0.80
H_a: p >0.80
What are the Type 1 and Type 2 errors for this study?

Question 38

Use the following information for questions:
The null hypothesis for p = proportion of students who own their own car is H₀: p = 0.10. The significance level is set at $\alpha$ = 0.05.

-The value of 10% was obtained ten years ago. The alternative hypothesis will state that the proportion of students who own their own car has increased from the value ten years ago. What is the alternative hypothesis for p?

Question 39

Use the following information for questions:
The null hypothesis for p = proportion of students who own their own car is H₀: p = 0.10. The significance level is set at $\alpha$ = 0.05.

-The results of the study gave a p-value of 0.01. What is the decision?

Question 40

Use the following information for questions:
The null hypothesis for p = proportion of students who own their own car is H₀: p = 0.10. The significance level is set at $\alpha$ = 0.05.

-The results of a study gave a p-value of 0.01. State your conclusion.

Question 41

Use the following information for questions:
The null hypothesis for p = proportion of students who own their own car is H₀: p = 0.10. The significance level is set at $\alpha$ = 0.05.

-Based on your decision in question 39, what mistake (error) could have been made?

Question 42

Use the following information for questions:
The null and alternative hypotheses for p = proportion of students who buy at least 3 textbooks in a semester is given below:
H₀: p = 0.80 (or p ? 0.80)
H_a: p > 0.80
The results of a study gave a p-value of 0.08. The results of this study also stated that the study results were not statistically significant.

-Give an example of a significance level the researchers performing the study could have used.

Question 43

Use the following information for questions:
The null and alternative hypotheses for p = proportion of students who buy at least 3 textbooks in a semester is given below:
H₀: p = 0.80 (or p ≤ 0.80)
H_a: p > 0.80
The results of a study gave a p-value of 0.08. The results of this study also stated that the study results were not statistically significant.
-State your conclusion.

Question 44

Use the following information for questions:
The null and alternative hypotheses for p = proportion of students who buy at least 3 textbooks in a semester is given below:
H₀: p = 0.80 (or p ≤ 0.80)
H_a: p > 0.80
The results of a study gave a p-value of 0.08. The results of this study also stated that the study results were not statistically significant.
-What mistake could the researchers have made?

Question 45

A Washington Post poll shows that concerns about housing payments have spiked despite some improvements in the overall economy. In all, 53 percent of the 900 American adults surveyed said they are "very concerned"or "somewhat concerned"about having the money to make their monthly payment. Let p represent the population proportion of all American adults who are "very concerned"or "somewhat concerned"about having the money to make their monthly payment. Which are the appropriate hypotheses to assess if a majority of American adults are worried about making their mortgage or rent payments?

A) H₀: p = 0.50 versus H_a: p > 0.50
B) H₀: p $\neq$ 0.50 versus H_a: p < 0.50
C) H₀: p = 0.53 versus H_a: p > 0.53
D) H₀: p = 0.50 versus H_a: p = 0.53

Question 46

A z-test for testing hypotheses about a population proportion is to be conducted. One condition for this z-test to be valid is that the population of all responses has a Normal distribution.

Question 47

A z-test for testing hypotheses about a population proportion is to be conducted.One condition for this z-test to be valid is that the sample size is adequately large enough.

Question 48

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.10
H_a: p ? 0.10
For each sample size n and sample proportion $\hat{p}$ compute the value of the z-statistic.

-Sample size n = 100 and sample proportion $\hat{p}$ = 0.10. z-statistic = ?

A) -1.00
B) 0.00
C) 0.10
D) 1.00

Question 49

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.10
H_a: p ? 0.10
For each sample size n and sample proportion $\hat{p}$ compute the value of the z-statistic.

-Sample size n = 100 and sample proportion $\hat{p}$ = 0.15. z-statistic = ?

A) -1.12
B) 0.04
C) 1.12
D) 1.67

Question 50

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.10
H_a: p ? 0.10
For each sample size n and sample proportion $\hat{p}$ compute the value of the z-statistic.

-Sample size n = 500 and sample proportion $\hat{p}$ = 0.04. z-statistic = ?

A) -6.84
B) -4.47
C) 4.47
D) 6.84

Question 51

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.10
H_a: p ? 0.10
For each sample size n and sample proportion $\hat{p}$ compute the value of the z-statistic.

-Sample size n = 500 and sample proportion $\hat{p}$ = 0.20. z-statistic = ?

A) -7.45
B) -5.59
C) 5.59
D) 7.45

Question 52

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p < 0.40
For each z-statistic, calculate the p-value for this hypothesis test.

-z-statistic = 0.50. p-value = ?

A) 0.0000
B) 0.3085
C) 0.5000
D) 0.6915

Question 53

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p < 0.40
For each z-statistic, calculate the p-value for this hypothesis test.

-z-statistic = 0.00. p-value = ?

A) 0.0000
B) 0.3085
C) 0.5000
D) 0.6915

Question 54

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p < 0.40
For each z-statistic, calculate the p-value for this hypothesis test.

-z-statistic = -1.50. p-value = ?

A) 0.0668
B) 0.1469
C) 0.8531
D) 0.9332

Question 55

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p < 0.40
For each z-statistic, calculate the p-value for this hypothesis test.

-z-statistic = 2.00. p-value = ?

A) 0.0228
B) 0.9332
C) 0.9545
D) 0.9772

Question 56

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p > 0.40
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = 0.50. p-value = ?

A) 0.0000
B) 0.3085
C) 0.5000
D) 0.6915

Question 57

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p > 0.40
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = 0.00. p-value = ?

A) 0.0000
B) 0.3085
C) 0.5000
D) 0.6915

Question 58

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p > 0.40
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic =-1.50. p-value = ?

A) 0.0668
B) 0.1469
C) 0.8531
D) 0.9332

Question 59

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p ? 0.40
H_a: p > 0.40
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = 2.00. p-value = ?

A) 0.0228
B) 0.9332
C) 0.9545
D) 0.9772

Question 60

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.70
H_a: p ? 0.70
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = 0.50. p-value = ?

A) 0.0000
B) 0.3085
C) 0.6170
D) 0.6915

Question 61

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.70
H_a: p ? 0.70
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = -0.40. p-value = ?

A) 0.3446
B) 0.4000
C) 0.6554
D) 0.6892

Question 62

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.70
H_a: p ? 0.70
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = 0.40. p-value = ?

A) 0.3446
B) 0.4000
C) 0.6554
D) 0.6892

Question 63

Use the following information for questions:
A hypothesis test for a population proportion p is given below:
H₀: p = 0.70
H_a: p ? 0.70
For each z-statistic, calculate the p-value for the hypothesis test.

-z-statistic = -1.00. p-value = ?

A) 0.1587
B) 0.3174
C) 0.6348
D) 0.8413

Question 64

Past data indicates an 80% (0.8) success rate in treating a certain medical problem. A new treatment is used on 100 patients in a clinical trial. It is successful in 87% (0.87) of the cases. What is the value of the z-score that can be used to test the null hypothesis that the success rate is 80%?

A) 7
B) 2
C) 1.75
D) -1.75

Question 65

Use the following information for questions:
An ESP experiment is done in which a participant guesses which of 4 cards the researcher has randomly picked, where each card is equally likely. This is repeated for 200 trials. The null hypothesis is that the subject is guessing, while the alternative is that the subject has ESP and can guess at higher than the chance rate.

-What is the correct statement of the null hypothesis that the person does not have ESP?

A) H₀: p = 0.5
B) H₀: p = 4/200
C) H₀: p = 1/4
D) H₀: p > 1/4

Question 66

Use the following information for questions:
An ESP experiment is done in which a participant guesses which of 4 cards the researcher has randomly picked, where each card is equally likely. This is repeated for 200 trials. The null hypothesis is that the subject is guessing, while the alternative is that the subject has ESP and can guess at higher than the chance rate.

-The subject actually gets 70 correct answers. Which of the following describes the probability represented by the p-value for this test?

A) The probability that the subject has ESP
B) The probability that the subject is just guessing.
C) The probability of 70 or more correct guesses if the subject has ESP.
D) The probability of 70 or more correct guesses if the subject is guessing at the chance rate.

Question 67

Use the following information for questions:
An ESP experiment is done in which a participant guesses which of 4 cards the researcher has randomly picked, where each card is equally likely. This is repeated for 200 trials. The null hypothesis is that the subject is guessing, while the alternative is that the subject has ESP and can guess at higher than the chance rate.

-Which of the following would be a Type 1 error in this situation?

A) Declaring somebody has ESP when they actually don't have ESP.
B) Declaring somebody does not have ESP when they actually do.
C) Analyzing the data with a confidence interval rather than a significance test.
D) Making a mistake in the calculations of the significance test.

Question 68

Use the following information for questions:
A sample of n = 200 college students is asked if they believe in extraterrestrial life and 120 of these students say that they do. The data are used to test H₀: p = 0.5 versus H_a: p > 0.5, where p is the population proportion of college students who say they believe in extraterrestrial life. The following Minitab output was obtained:


-What is the correct description of the area that equals the p-value for this problem?

A) The area to the right of 0.60 under a standard normal curve.
B) The area to the right of 2.83 under a standard normal curve.
C) The area to the right of -2.83 under the standard normal curve.
D) The area between 0.532105 and 0.667895 under a standard normal curve.

Question 69

Use the following information for questions:
A sample of n = 200 college students is asked if they believe in extraterrestrial life and 120 of these students say that they do. The data are used to test H₀: p = 0.5 versus H_a: p > 0.5, where p is the population proportion of college students who say they believe in extraterrestrial life. The following Minitab output was obtained:


-Suppose that the alternative hypothesis had been H_a: p ? 0.5. What would have been the p-value of the test?

A) 0.002
B) 0.001
C) 0.004
D) 0.5

Question 70

Use the following information for questions:
A sample of n = 200 college students is asked if they believe in extraterrestrial life and 120 of these students say that they do. The data are used to test H₀: p = 0.5 versus H_a: p > 0.5, where p is the population proportion of college students who say they believe in extraterrestrial life. The following Minitab output was obtained:


-Using a 5% significance level, what is the correct decision for this significance test?

A) Fail to reject the null hypothesis because the p-value is greater than 0.05.
B) Fail to reject the null hypothesis because the p-value is less than 0.05.
C) Reject the null hypothesis because the p-value is greater than 0.05.
D) Reject the null hypothesis because the p-value is less than 0.05.

Question 71

Use the following information for questions:
A sample of n = 200 college students is asked if they believe in extraterrestrial life and 120 of these students say that they do. The data are used to test H₀: p = 0.5 versus H_a: p > 0.5, where p is the population proportion of college students who say they believe in extraterrestrial life. The following Minitab output was obtained:


-Using a 5% significance level, what is the correct conclusion for this significance test?

A) The proportion of college students who say they believe in extraterrestrial life is equal to 50%.
B) The proportion of college students who say they believe in extraterrestrial life is not equal to 50%.
C) The proportion of college students who say they believe in extraterrestrial life seems to be greater than 50%.
D) The proportion of college students who say they believe in extraterrestrial life seems to be equal to 60%.

Question 72

Use the following information for questions:
A sample of n = 200 college students is asked if they believe in extraterrestrial life and 120 of these students say that they do. The data are used to test H₀: p = 0.5 versus H_a: p > 0.5, where p is the population proportion of college students who say they believe in extraterrestrial life. The following Minitab output was obtained:


-Based on the decision made in question 70, what mistake could have been made?

A) Type 1.
B) Type 2.
C) Neither one; the p-value is so small that no mistake could have been made.

Question 73

About 90% of the general population is right-handed. A researcher speculates that artists are less likely to be right-handed than the general population. In a random sample of 100 artists, 83 are right-handed. Which of the following best describes the p-value for this situation?

A) The probability that the population proportion of artists who are right-handed is 0.90.
B) The probability that the population proportion of artists who are right-handed is 0.83.
C) The probability the sample proportion would be as small as 0.83, or even smaller, if the population proportion of artists who are right-handed is actually 0.90.
D) The probability that the population proportion of artists who are right-handed is less than 0.90, given that the sample proportion is 0.83.

Question 74

Consider testing the alternative hypothesis that the proportion of adult Canadians opposed to same-sex marriage in Canada is less than 0.5. The test was conducted based on a poll of n = 1003 adults and it had a p-value of 0.102. Which of the following describes the probability represented by the p-value for this test?

A) It is the probability that fewer than half of all adults in Canada that year were opposed to same-sex marriage.
B) It is the probability that more than half of all adult Canadians that year were opposed to same-sex marriage.
C) It is the probability that a sample of 1003 adults in Canada that year would result in 48% or fewer saying they are opposed to same-sex marriage, given that a majority (over 50%) of Canadian adults actually were opposed that year.
D) It is the probability that a sample of 1003 adults in Canada that year would result in 48% or fewer saying they are opposed to same-sex marriage, given that 50% of Canadian adults actually were opposed that year.

Question 75

Use the following information for questions:
A researcher examined the folklore that women can predict the sex of their unborn child better than chance would suggest. She asked 104 pregnant women to predict the sex of their unborn child, and 57 guessed correctly. Using these data, the researcher created the following Minitab output.

-Based on the information in the output, what is the appropriate conclusion the researcher can make about p = proportion of pregnant women who can correctly predict the sex of their unborn child?

A) There is statistically significantly evidence against the null hypothesis that p = 0.5.
B) There is not statistically significant evidence against the null hypothesis that p = 0.5.
C) There is statistically significant evidence against the null hypothesis that p = 0.548.
D) There is not statistically significant evidence against the null hypothesis that p = 0.548.

Question 76

Use the following information for questions:
A researcher examined the folklore that women can predict the sex of their unborn child better than chance would suggest. She asked 104 pregnant women to predict the sex of their unborn child, and 57 guessed correctly. Using these data, the researcher created the following Minitab output.

-Which choice describes how the p-value was computed in this situation?

A) The probability that a z-score would be greater than or equal to 0.98.
B) The probability that a z-score would be less than or equal to 0.98.
C) The total of the probabilities that a z-score is greater than or equal to 0.98 and less than or equal to-0.98.
D) The probability that a z-score would be between -0.98 and 0.98.

Question 77

A null hypothesis is that the probability is 0.7 that a new drug will provide relief in a randomly selected patient. The alternative is that the probability of relief is greater than 0.7. Suppose the treatment is used on 500 patients and there are 380 successes. How would a p-value be calculated in this situation?

A) Find the chance of 380 or more successes, calculated assuming the true success rate is greater than 0.7.
B) Find the chance of 380 or more successes, calculated assuming the true success rate is 0.7.
C) Find the chance of fewer than 380 successes, calculated assuming the true success rate is greater than 0.7.
D) Find the chance of fewer than 380 successes, calculated assuming true success rate is 0.7.

Question 78

The p-value for a one-sided test for a population proportion was 0.02. The p-value for the corresponding two-sided test would be:

A) .01
B) .02
C) .04
D) It depends on whether the one-sided test had a "greater than" sign or a "less than" sign in the alternative hypothesis.

Question 79

The p-value for a two-sided test for a population proportion was 0.04. The p-value for a one-sided test would be:

A) .02
B) .04
C) .08
D) It depends on whether the one-sided test had a "greater than" sign or a "less than" sign in the alternative hypothesis.

Question 80

Suppose a 95% confidence interval for p, the proportion of drivers who admit that they sometimes run red lights when no one is around, is 0.29 to 0.38. Which of the following statements is false?

A) A test of H₀: p = 0.3 versus H_a: p ?0.3 would not be rejected using $\alpha$ = 0.05.
B) A test of H₀: p = 0.5 versus H_a: p ?0.5 would be rejected using $\alpha$ = 0.05.
C) It is plausible that about 37% of all drivers would admit that they sometimes run red lights when no one is around.
D) It is plausible that a majority of all drivers would admit that they sometimes run red lights when no one is around.