Part 1 of 3 - 11.0/ 11.0 Points
Question 1 of 20
1.0/ 1.0 Points
Which of the following values is not typically used for f$alpha f$ ?
A.0.05
B.0.10
C.0.01
Correct D.0.50
Answer Key: D
Question 2 of 20
1.0/ 1.0 Points
A severe storm has an average peak wave height of 16.4 feet for waves hitting the shore. Suppose that a storm is in progress with a severe storm class rating. Let us say that we want to set up a statistical test to see if the wave action (i.e., height) is dying down or getting worse. If you wanted to test the hypothesis that the waves are dying down, what would you use for the alternate hypothesis? Is the P-value area on the left, right, or on both sides of the mean?
A.H1: \f$\mu \f$ is greater than 16.4 feet; the P-value area is on both sides of the mean
B.H1: \f$\mu \f$ is not equal to 16.4 feet; the P-value area is on the right of the mean
Correct C.H1: \f$\mu \f$ is less than 16.4 feet; the P-value area is on the left of the mean
D.H1: \f$\mu \f$ is greater than 16.4 feet; the P-value area is on the left of the mean
Answer Key: C
Question 3 of 20
1.0/ 1.0 Points
You conduct a hypothesis test and you observe values for the sample mean and sample standard deviation when n = 25 that do not lead to the rejection of H0. You calculate a p-value of 0.0667. What will happen to the p-value if you observe the same sample mean and standard deviation for a sample size larger than 25?
A.The p – value stays the same
Correct B.The p – value decreases
C.The p – value may increase or decrease
D.The p – value increases
Answer Key: B
Question 4 of 20
1.0/ 1.0 Points
A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?
At the a = .01 level of significance, what is your conclusion?
A.
Reject H0. At the \f$\alpha \f$ = .01 level of significance, there is not enough evidence to support the claim that this technician’s true variance is larger than the target accuracy.
Correct B.Do not reject H0. At the \f$\alpha \f$ = .01 level of significance there is not sufficient evidence to suggest that this technician’s true variance is greater than the target accuracy.
C.Cannot determine
D.Reject H0. At the \f$\alpha \f$ = .01 level of significance, there is enough evidence to support the claim that this technician’s variance is larger than the target accuracy.
Answer Key: B
Question 5 of 20
1.0/ 1.0 Points
A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?
State the null and alternative hypotheses.
Correct A.H0: s2 ≤ 1.2, H1: s2 > 1.2
B.H0: s2 ≠ 1.2, H1: s2 = 1.2
C.H0: s2 ≥ 1.2, H1: s2 ≠ 1.2
D.H0: s2 < 1.2, H1: s2 ≠ 1.2
Answer Key: A
Question 6 of 20
1.0/ 1.0 Points
In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.
At the a = .05 level of significance, does the nutritionist have enough evidence to reject the writer’s claim?
A.Cannot Determine
Correct B.No
C.Yes
Answer Key: B
Question 7 of 20
1.0/ 1.0 Points
A lab technician is tested for her consistency by taking multiple measurements of cholesterol levels from the same blood sample. The target accuracy is a variance in measurements of 1.2 or less. If the lab technician takes 16 measurements and the variance of the measurements in the sample is 2.2, does this provide enough evidence to reject the claim that the lab technician’s accuracy is within the target accuracy?
Compute the value of the appropriate test statistic.
A.t = 27.50
B.z = 1.65
C.\f$\chi ^{2}\f$ = 30.58
Correct D.\f$\chi ^{2}\f$ = 27.50
Answer Key: D
Question 8 of 20
1.0/ 1.0 Points
Suppose that the mean time for a certain car to go from 0 to 60 miles per hour was 7.7 seconds. Suppose that you want to test the claim that the average time to accelerate from 0 to 60 miles per hour is longer than 7.7 seconds. What would you use for the alternative hypothesis?
A.H1: \f$\mu \f$ < 7.7 seconds
Correct B.H1: \f$\mu \f$ > 7.7 seconds
C.H1: \f$\mu \geq \f$ 7.7 seconds
D.H1: \f$\mu \f$ = 7.7 seconds
Answer Key: B
Question 9 of 20
1.0/ 1.0 Points
Smaller p-values indicate more evidence in support of the:
Correct A.alternative hypothesis
B.null hypothesis
C.quality of the researcher
D.the reduction of variance
Answer Key: A
Question 10 of 20
1.0/ 1.0 Points
In an article appearing in Today’s Health a writer states that the average number of calories in a serving of popcorn is 75. To determine if the average number of calories in a serving of popcorn is different from 75, a nutritionist selected a random sample of 20 servings of popcorn and computed the sample mean number of calories per serving to be 78 with a sample standard deviation of 7.
State the null and alternative hypotheses.
A.H0: \f$\mu \f$ \f$\leq \f$ 75, H1: \f$\mu \f$ > 75
Correct B.H0: \f$\mu \f$ = 75, H1: \f$\mu \f$ ≠ 75
C.H0: \f$\mu \f$ \f$\geq \f$ 75, H1: \f$\mu \f$ < 75
D.H0: \f$\mu \f$ = 75, H1: \f$\mu \f$ > 75
Answer Key: B
Question 11 of 20
1.0/ 1.0 Points
If a teacher is trying to prove that a new method of teaching economics is more effective than a traditional one, he/she will conduct a:
A.confidence interval
B.two-tailed test
C.point estimate of the population parameter
Correct D.one-tailed test
Answer Key: D
Part 2 of 3 - 1.0/ 6.0 Points
Question 12 of 20
0.0/ 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
A firm that produces light bulbs claims that their lightbulbs last 1500 hours, on average. You wonder if the average might differ from the 1500 hours that the firm claims. To explore this possibility you take a random sample of n = 25 light bulbs purchased from this firm and record the lifetime (in hours) of each bulb. You then conduct an appopriate test of hypothesis. Some of the information related to the hypothesis test is presented below.
Test of H0: f$mu f$ = 1500 versus H1: f$ mu
eq f$ 1500
Sample mean 1509.5
Std error of mean 4.854
Assuming the life length of this type of lightbulb is normally distributed, what is the p-value associated with this test? Place your answer, rounded to 3 decimal places, in the blank. For example, 0.234 would be a legitimate entry. Correct1.711
Answer Key: 0.062
Question 13 of 20
0.0/ 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
A statistician wishes to test the claim that the standard deviation of the weights of firemen is greater than 25 pounds. To do so, she selected a random sample of 30 firemen and found s = 27.2 pounds.
Assuming that the weights of firemen are normally distributed, if the statistician wanted to test her research hypothesis at the .05 level of significance, what is the critical value?
Place your answer, rounded to 3 decimal places, in the blank. For example, 23.456 would be a legitimate entry. Correct34.329
Answer Key: 42.557
Question 14 of 20
1.0/ 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
A medical doctor wishes to test the claim that the standard deviation of the systolic blood pressure of deep sea divers is less than 450. To do so, she selected a random sample of 20 divers and found s = 432.
Assuming that the systolic blood pressures of deep sea divers are normally distributed, if the doctor wanted to test her research hypothesis at the .01 level of significance, what is the critical value?
Place your answer, rounded to 3 decimal places, in the blank. For example, 4.567 would be a legitimate entry. Correct 7.633
Answer Key: 7.633
Question 15 of 20
0.0/ 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
Let x be a random variable representing dividend yield of Australian bank stocks. We may assume that x has a normal distribution with f$sigma f$ = 2.8%. A random sample of 16 Australian bank stocks has a sample mean dividend yield of 8.91%. For the entire Australian stock market, the mean dividend yield is f$mu f$ = 6.4%. If you wanted to test, at a .05 level of significance, to determine if these data indicate that the dividend yield of all Australian bank stocks is higher than 6.4% what is the critical value that you would use? Place your answer, rounded to 2 decimal places, in the blank. For example, 2.345 would be a legitimate entry. Correct7.55
Answer Key: 1.65
Question 16 of 20
0.0/ 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
The ABC battery company claims that their batteries last 100 hours, on average. You decide to conduct a test to see if the company's claim is true. You believe that the mean life may be different from the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below.
Test of H0: f$mu f$ = 100 versus H1: f$mu
eq f$ 100
Sample mean 98.5
Std error of mean 0.777
Assuming the life length of batteries is normally distributed, if you wish to conduct this test at the 0.05 level of significance, what are the critical values that you should use? Place the smaller critical value, rounded to 3 decimal places, in the first blank. For example, -1.234 would be a legitimate entry. Correct-1.932 . Place the larger critical value, rounded to 3 decimal places, in the second blank. For example, 1.234 would be a legitimate entry. Correct-1.930
Answer Key: -2.093, 2.093
Question 17 of 20
0.0/ 1.0 Points
Accepted characters: numbers, decimal point markers (period or comma), sign indicators (-), spaces (e.g., as thousands separator, 5 000), "E" or "e" (used in scientific notation). NOTE: For scientific notation, a period MUST be used as the decimal point marker.
Complex numbers should be in the form (a + bi) where "a" and "b" need to have explicitly stated values.
For example: {1+1i} is valid whereas {1+i} is not. {0+9i} is valid whereas {9i} is not.
The ABC battery company claims that their batteries last at least 100 hours, on average. Your experience with their batteries has been somewhat different, so you decide to conduct a test to see if the company's claim is true. You believe that the mean life is actually less than the 100 hours the company claims. You decide to collect data on the average battery life (in hours) of a random sample of n = 20 batteries. Some of the information related to the hypothesis test is presented below.
Test of H0: f$mu geq f$ 100 versus H1: f$mu< f$ 100
Sample mean 98.5
Std error of mean 0.777
Assuming the life length of batteries is normally distributed, if you wish to conduct this test using a .05 level of significance, what is the critical value that you should use? Place your answer, rounded to 3 decimal places in the blank. For example, -1.234 would be a legitimate entry. Correct-1931
Answer Key: -1.729
Part 3 of 3 - 3.0/ 3.0 Points
Question 18 of 20
1.0/ 1.0 Points
Using the confidence interval when conducting a two-tailed test for the population proportion p, we reject the null hypothesis if the hypothesized value for p falls inside the confidence interval.
Correct
True
False
Answer Key: False
Question 19 of 20
1.0/ 1.0 Points
In order to determine the p-value, it is unnecessary to know the level of significance.
Correct
True
False
Answer Key: True
Question 20 of 20
1.0/ 1.0 Points
The smaller the p–value, the more evidence there is in favor of the alternative hypothesis.
Correct
True
False
Answer Key: True
Quick Reply
