You have hired a polling organization to take a simple random sample from a box of 200,000 tickets and estimate the percentage of 1s in the box. Unknown to them, the box contains 50% 0s and 50% 1s. How far off should you expect them to be if they draw 50,000 tickets?
Answer
a.
1.50%
b.
0.17%
c.
0.20%
d.
0.23%
e.
0.19%
5.92 points
Question 2
In a certain city, there are 100,000 persons age 18 to 24. A simple random sample of 400 such persons is drawn, of whom 220 turn out to be currently enrolled in college. Estimate the percentage of all persons age 18 to 24 in that city who are currently enrolled in college.
Answer
a.
50%
b.
41.1%
c.
45%
d.
55%
e.
39.6%
5.88 points
Question 3
In a certain city, there are 100,000 persons age 18 to 24. A simple random sample of 400 such persons is drawn, of whom 220 turn out to be currently enrolled in college. Find the SE% for the percentage of all persons age 18 to 24 in that city who are currently enrolled in college.
Answer
a.
2.49%
b.
6.88%
c.
none of these
d.
2.19%
e.
2.20%
5.88 points
Question 4
In a certain city, there are 100,000 persons age 18 to 24. A simple random sample of 400 such persons is drawn, of whom 220 turn out to be currently enrolled in college. If possible, find the lower end point for the 90% confidence interval for the percentage of all persons age 18 to 24 in that city who are currently enrolled in college.
Answer
a.
50.89%
b.
not possible
c.
49.82%
d.
none of these
e.
35.22%
5.88 points
Question 5
For a cluster sample, the estimates of the halves came in at 62.70 and 58.85. Find the Standard Error.
Answer
a.
1.15
b.
1.925
c.
0.30
d.
0.20
e.
110.9
5.88 points
Question 6
In a month, the Current Population Survey sample amounted to 100,000 people. Of them, 62,000 were employed, and 3,000 were unemployed. True or False: The Bureau would estimate that 65% of the population was in the labor force.
Answer
a.
False
b.
True
5.88 points
Question 7
In a month, the Current Population Survey sample amounted to 100,000 people. Of them, 62,000 were employed, and 3,000 were unemployed. True or False: The Bureau would estimate the percentage of the population who are unemployed as 4.62%.
Answer
a.
True
b.
False
5.88 points
Question 8
In a month, the Current Population Survey sample amounted to 100,000 people. Of them, 62,000 were employed, and 3,000 were unemployed. True or False: The Bureau would estimate the total number unemployed in the population by using weights obtained by dividing the sample into groups by age, sex, race, area of residence, and so on.
Answer
a.
True
b.
False
5.88 points
Question 9
The probability histogram for the average of the draws will follow the normal curve, even if the contents of the box do not, as long as the histogram is put into standard units, and the number of draws is large.
Answer
a.
False
b.
True
5.88 points
Question 10
The average of a box of tickets is 140. The SD is 10. If we make 400 draws at random, what is the standard error for the average?
Answer
a.
none of these
b.
5
c.
20
d.
200
e.
0.5
5.88 points
Question 11
The tickets in a box have an SD equal to 10. Their average is 120. Two hundred tickets are drawn at random. Find the chance that the average of these two hundred draws is between 118 and 120?
Answer
a.
none of these
b.
95%
c.
100%
d.
75%
e.
68%
5.88 points
Question 12
One kind of plant has only white flowers and pink flowers. According to a genetic model, the offsprings of a certain cross have a 60% chance to be pink-flowering, and a 40% chance to be white-flowering, independently of one another. Two hundred seeds of such a cross are raised, and 130 turn out to be pink-flowering. We wish to determine if the data are consistent with the model.(use one-tailed test) What is the expected value for the percentage of pink-flowering plants?
Answer
a.
60%
b.
50%
c.
75%
d.
34%
e.
40%
5.88 points
Question 13
One kind of plant has only white flowers and pink flowers. According to a genetic model, the offsprings of a certain cross have a 60% chance to be pink-flowering, and a 40% chance to be white-flowering, independently of one another. Two hundred seeds of such a cross are raised, and 130 turn out to be pink-flowering. We wish to determine if the data are consistent with the model.(use one-tailed test) What is the observed value for the percentage of pink-flowering plants?
Answer
a.
65%
b.
75%
c.
60%
d.
50%
e.
40%
5.88 points
Question 14
One kind of plant has only white flowers and pink flowers. According to a genetic model, the offsprings of a certain cross have a 60% chance to be pink-flowering, and a 40% chance to be white-flowering, independently of one another. Two hundred seeds of such a cross are raised, and 130 turn out to be pink-flowering. We wish to determine if the data are consistent with the model.(use one-tailed test) Find the value of the SE%.
Answer
a.
2.99%
b.
1.64%
c.
2.11%
d.
3.46%
e.
1.93%
5.88 points
Question 15
One kind of plant has only white flowers and pink flowers. According to a genetic model, the offsprings of a certain cross have a 60% chance to be pink-flowering, and a 40% chance to be white-flowering, independently of one another. Two hundred seeds of such a cross are raised, and 130 turn out to be pink-flowering. We wish to determine if the data are consistent with the model.(use one-tailed test) Find the value of the test statistic.
Answer
a.
1.31
b.
1.45
c.
2.31
d.
2.01
e.
0.33
5.88 points
Question 16
One kind of plant has only white flowers and pink flowers. According to a genetic model, the offsprings of a certain cross have a 60% chance to be pink-flowering, and a 40% chance to be white-flowering, independently of one another. Two hundred seeds of such a cross are raised, and 130 turn out to be pink-flowering. We wish to determine if the data are consistent with the model.(use one-tailed test) Find the p-value.
Answer
a.
4.95%
b.
none of these
c.
3.59%
d.
3.28%
e.
2.10%
5.88 points
Question 17
One kind of plant has only white flowers and pink flowers. According to a genetic model, the offsprings of a certain cross have a 60% chance to be pink-flowering, and a 40% chance to be white-flowering, independently of one another. Two hundred seeds of such a cross are raised, and 130 turn out to be pink-flowering. We wish to determine if the data are consistent with the model.(use one-tailed test) Are the data consistent with the model?
Answer
a.
No
b.
Yes
FICO Scores The FICO credit rating scores obtained in a simple random sample are listed below. As of this writing, the reported mean FICO score was 678. Do these sample FICO scores appear to be consistent with the reported mean?
714 751 664 789 818 779 698 836 753 834 693 802
FICO Scores – A simple random sample of FICO credit rating scores is listed below, As of this writing, the mean FICO score was reported to be 678. Based on these results, is a FICO score of 500 unusual Why or why not?
714 751 664 789 818 779 698 836 753 834 693 802
(714+751+664+789+818+779+698+836+753+834+693+802)/12 = 760.97
Answer: No, 760.97 does not equal to 678
Add all numbers then devide by the number of the above numbers (we have 12 in total) and that will give you a mean.
A simple random sample of FICO credit rating scores is listed below:
714 751 664 789 818 779 698 836 753 834 693 802
Find range, variance, and standard deviation.