A poll of 811 adults aged 18 or older asked about purchases that they intendend to make for the upcoming holiday season. One of the questions asked about what kind of gift they intendend to buy for the person on whom they would spend the most. Clothing was the first choice of 487 people. Give a 99% confidence interval for the proportion of people in this population who intend to buy clothing as their first choice. (Use the sample proportion p(hat)=X/n for estimation)
Question 1 options:
a {0.5352, 0.6648}
b {0.5399, 0.6601}
c {0.5411, 0.6589}
d {0.5499, 0.6501}
{0.5562, 0.6448}
Question 2 (2 points)
In a survey of 1 280 student loan borrowers, there were 1050 borrowers whose total debt was $10,000 or more. Of these, 192 left school without completing a degree. Consider the population to be borrowers whose total debt was $10,000 or more.
Give the left endpoint (lower boundary) of a 95% confidence interval for the proportion of borrowers who left school without completing a degree in this population.
Use the sample proportion p(hat)=X/n for estimation
Your Answer: (fill in the blank)
Question 3
For the problem in question 2 give the right endpoint (upper boundary) of a 95% confidence interval for the proportion.
Your Answer: (fill in the blank)
Question 4
The P-value of a test of a null hypothesis is
Question 4 options:
A: the probability, assuming the null hypothesis is true, that the
test statistic will take a value at least as extreme as that
actually observed.
B: the probability, assuming the null hypothesis is false, that
the test statistic will take a value at least as extreme as
that actually observed.
C: the probability that the null hypothesis is true.
D: the probability that the null hypothesis is false.
Question 5
P-value for a significance test is 0.022. Do you reject the null hypothesis at significant level 0.05?
Question 5 options:
A: Yes, I reject Ho.
B: No, I don't reject Ho.
C: There is not enough information to make decision.
Question 6
Write the null and alternative hypotheses you would use to test each situation.
a) In the 1950’s only about 40% of high school graduates went on to college. Has the percentage changed?
b) 20% of cars of a certain model have needed costly transmission work after being driven between 50,000 and 100,000 miles. The manufacturer hopes that a redesign of a transmission component has solved this problem
c) We field-test a new flavor soft drink, planning to market it only if we are sure that over 60% of the people like the flavor.
In each situation decide is the test left-sided, right-sided or two-sided.
Question 6 options:
a)
c)
b)
1. Left-sided ( Ho: P = Po, Ha: P < Po).
2. Two-sided ( Ho: P = Po, Ha: P is not equal to Po).
3. Right-sided ( Ho: P = Po, Ha: P > Po).
Question 7
The seller of a loaded ide claims that it will favor the outcome 6. We don’t believe that claim, and roll the die 200 times to test an appropriate hypothesis. Our P-value turns out to be .03. Which conclusion is appropriate?
At significance level 0.05 which conclusion is appropriate?
Question 7 options:
A: There's a 3% chance that the die is fair.
B: There's a 97% chance that the die is fair.
C: There's a 3% chance that a loaded die could randomly produce the results we observed, so it is reasonable to conclude that the die is fair.
D: There's a 3% chance that a fair die could randomly produce the results we observed, so it is reasonable to conclude that the die is loaded.
Question 8
In November 2001, the Ag Globe Trotter news-letter reported that 90% of adults drink milk. A regional farmers’ organization planning a new marketing campaign across its multicounty area polls a random sample of 750 adults living there. In this sample, 657 people said that they drink milk. Do these responses provide strong evidence that the 90% figure is not accurate for this region? Correct the mistakes you find in a student’s attempt to test an appropriate hypothesis.
Ho
̂ = .9
HÂ <.9
SYS,750 ≥ 10
= .876; SD(P̂) =
= .012
z =
p = -(z > -2) = .977
There is more than a 97% chance that the stated percentage is correct for this region.
Question 8 options: (Fill in the blank)
Question 9
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. Write appropriate hypothesis.
Question 9 options:
A; Ho: P is equal to 0.31.
Ha: P is less than 0.31.
B: Ho: P is equal to 0.31.
Ha: P is greater than 0.20.
C: Ho: P is less than 0.31.
Ha: P is equal to 0.31.
D: Ho: P is greater than 0.31.
Ha: P is equal to 0.31.
E: Ho: P is equal to 0.31.
Ha: P is not equal to 0.31.
F: Ho: P is not equal to 0.31.
Ha: P is equal to 0.31.
G: Ho: P is equal to 0.32.
Ha: P is not equal to 0.32.
H: Ho: P is equal to 0.32.
Ha: P is greater than 0.32.
I: Ho: P is equal to 0.32.
Ha: P is less than 0.32.
Question 10
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. Check the assumptions and conditions.Are the assumptions and conditions nessesary for inference satisfied?
Question 10 options:
A: 10% Condition.
B: Randomization Condition.
C: Independence Assumption.
D: Success/Failure Condition.
1. Assumption (condition) is satisfied.
2. Assumption (condition) is not satisfied.
Question 11
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. Perform the test and find the P-value.
Question 11 options:
A: 0..024
B: 0.032
C: 0.048
D: 0.064
E: 0.096
F: -0.056
Question 12
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. State your conclusion using 5% level of significance.
Hint: If P-value is less than or equal to 0.05 reject Ho.
Question 12 options:
A: Fail to reject Ho. There is no evidence of a change in education level among mothers.
B: Rreject Ho. There is enough evidence of a change in education level among mothers.
Question 1 options:
a {0.5352, 0.6648}
b {0.5399, 0.6601}
c {0.5411, 0.6589}
d {0.5499, 0.6501}
{0.5562, 0.6448}
Question 2 (2 points)
In a survey of 1 280 student loan borrowers, there were 1050 borrowers whose total debt was $10,000 or more. Of these, 192 left school without completing a degree. Consider the population to be borrowers whose total debt was $10,000 or more.
Give the left endpoint (lower boundary) of a 95% confidence interval for the proportion of borrowers who left school without completing a degree in this population.
Use the sample proportion p(hat)=X/n for estimation
Your Answer: (fill in the blank)
Question 3
For the problem in question 2 give the right endpoint (upper boundary) of a 95% confidence interval for the proportion.
Your Answer: (fill in the blank)
Question 4
The P-value of a test of a null hypothesis is
Question 4 options:
A: the probability, assuming the null hypothesis is true, that the
test statistic will take a value at least as extreme as that
actually observed.
B: the probability, assuming the null hypothesis is false, that
the test statistic will take a value at least as extreme as
that actually observed.
C: the probability that the null hypothesis is true.
D: the probability that the null hypothesis is false.
Question 5
P-value for a significance test is 0.022. Do you reject the null hypothesis at significant level 0.05?
Question 5 options:
A: Yes, I reject Ho.
B: No, I don't reject Ho.
C: There is not enough information to make decision.
Question 6
Write the null and alternative hypotheses you would use to test each situation.
a) In the 1950’s only about 40% of high school graduates went on to college. Has the percentage changed?
b) 20% of cars of a certain model have needed costly transmission work after being driven between 50,000 and 100,000 miles. The manufacturer hopes that a redesign of a transmission component has solved this problem
c) We field-test a new flavor soft drink, planning to market it only if we are sure that over 60% of the people like the flavor.
In each situation decide is the test left-sided, right-sided or two-sided.
Question 6 options:
a)
c)
b)
1. Left-sided ( Ho: P = Po, Ha: P < Po).
2. Two-sided ( Ho: P = Po, Ha: P is not equal to Po).
3. Right-sided ( Ho: P = Po, Ha: P > Po).
Question 7
The seller of a loaded ide claims that it will favor the outcome 6. We don’t believe that claim, and roll the die 200 times to test an appropriate hypothesis. Our P-value turns out to be .03. Which conclusion is appropriate?
At significance level 0.05 which conclusion is appropriate?
Question 7 options:
A: There's a 3% chance that the die is fair.
B: There's a 97% chance that the die is fair.
C: There's a 3% chance that a loaded die could randomly produce the results we observed, so it is reasonable to conclude that the die is fair.
D: There's a 3% chance that a fair die could randomly produce the results we observed, so it is reasonable to conclude that the die is loaded.
Question 8
In November 2001, the Ag Globe Trotter news-letter reported that 90% of adults drink milk. A regional farmers’ organization planning a new marketing campaign across its multicounty area polls a random sample of 750 adults living there. In this sample, 657 people said that they drink milk. Do these responses provide strong evidence that the 90% figure is not accurate for this region? Correct the mistakes you find in a student’s attempt to test an appropriate hypothesis.
Ho
̂ = .9HA
̂ <.9SYS,750 ≥ 10
z =
p = -(z > -2) = .977
There is more than a 97% chance that the stated percentage is correct for this region.
Question 8 options: (Fill in the blank)
Question 9
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. Write appropriate hypothesis.
Question 9 options:
A; Ho: P is equal to 0.31.
Ha: P is less than 0.31.
B: Ho: P is equal to 0.31.
Ha: P is greater than 0.20.
C: Ho: P is less than 0.31.
Ha: P is equal to 0.31.
D: Ho: P is greater than 0.31.
Ha: P is equal to 0.31.
E: Ho: P is equal to 0.31.
Ha: P is not equal to 0.31.
F: Ho: P is not equal to 0.31.
Ha: P is equal to 0.31.
G: Ho: P is equal to 0.32.
Ha: P is not equal to 0.32.
H: Ho: P is equal to 0.32.
Ha: P is greater than 0.32.
I: Ho: P is equal to 0.32.
Ha: P is less than 0.32.
Question 10
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. Check the assumptions and conditions.Are the assumptions and conditions nessesary for inference satisfied?
Question 10 options:
A: 10% Condition.
B: Randomization Condition.
C: Independence Assumption.
D: Success/Failure Condition.
1. Assumption (condition) is satisfied.
2. Assumption (condition) is not satisfied.
Question 11
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. Perform the test and find the P-value.
Question 11 options:
A: 0..024
B: 0.032
C: 0.048
D: 0.064
E: 0.096
F: -0.056
Question 12
The National Center for Education Statistics monitors many aspects of elementary and secondary education nationwide. Their 1996 numbers are often used as a baseline to assess changes. In 1996, 31% of students reported that their mothers had graduated from college. In 2000, responses from 8368 students found that this figure had grown to 32%. Set up null and alternative hypotheses about the population proportion P. State your conclusion using 5% level of significance.
Hint: If P-value is less than or equal to 0.05 reject Ho.
Question 12 options:
A: Fail to reject Ho. There is no evidence of a change in education level among mothers.
B: Rreject Ho. There is enough evidence of a change in education level among mothers.