Questions -
For questions 1 and 2 classify the measurement types in each of the following examples as:
A. Nominal data
B. Ordinal data
C. Interval data
_______ Q1. An individual's opinion of the statement "marijuana should be taxed and legalized" as strongly disagree, disagree, neutral, agree or strongly agree.
________Q2. Self-identified race
Q3. If when variable X decreases, variable Y increases, the correlation is said to be:
A. Strong
B. Positive
C. Weak
D. Negative
Q4. If the correlation between variables X and Y is found to be - 1.16:
A. The relationship is negative
B. The relationship is strong
C. We have miscalculated
D. The distribution is skewed
Q5. There are three children ages 8, 9, and 10 in a room. If two more 9 year old children enter the room the
A. Mean age will stay the same but the variance will increase
B. Mean age will stay the same but the variance will decrease
C. Mean age and variance will stay the same
D. Mean age and variance will increase
Q6. The number of undergraduates at Johns Hopkins University is approximately 2000, while the number at University of Missouri is approximately 30,000. At both schools, a simple random sample of about 3% of the undergraduates is taken. We can conclude that
A. The sampling distribution from which the Johns Hopkins sample was taken has less sampling variability than that of MU.
B. The sampling distribution from which the Johns Hopkins sample was taken has more sampling variability than that of MU.
C. The sample from Johns Hopkins has the same variability than that from MU.
D. It is impossible to make any statements about sampling variability of the two samples because the students are different.
Please use the following information for questions 7 through 9:
You are interested in residential mobility among college students. To study this you take a random sample of 20 MU seniors and ask them how many times they have moved since beginning college. You receive the following responses:
|
Table 1. Residential Mobility among Sampled University of Missouri Students
|
|
Times Moved
|
F
|
Cumulative Frequency
|
Percent
|
Cumulative Percent
|
|
1
|
2
|
2
|
10
|
10
|
|
2
|
4
|
6
|
20
|
30
|
|
3
|
3
|
9
|
15
|
45
|
|
4
|
6
|
15
|
30
|
75
|
|
5
|
3
|
18
|
15
|
90
|
|
6
|
2
|
20
|
10
|
100
|
|
Total
|
20
|
|
100
|
|
Q7. What percent of sampled respondents have moved three times or less?
A. 9
B. 15
C. 45
D. 75
Q8. What percent of sampled respondents have moved two times or more?
A. 6
B. 20
C. 30
D. 90
Q9. What is the mode of your sample?
A. 2 moves
B. 3 moves
C. 4 moves
D. 5 moves
Q10. For a normal curve, the probability of a random observation having a value between X1 and X2 is:
A. The proportion of cases between the mean and X2.
B. The proportion of cases between the right limit of the curve and X2.
C. The proportion of cases between X1 and X.
D. The 95 percent confidence interval around the mean of X1 and X2.
Q11. All of the following are measures of variability in a sample except:
A. The range.
B. The IQR.
C. The variance.
D. The mode
Please use the following information for questions 12 and 13:
The following are probabilities for outcomes of "at bats" for the population of MU intramural softball teams:
Out: .350
Single: .250
Double: .150
Triple: .100
Home run: .050
Walk: .100
Q12. What is the probability that a batter will get a double or a triple?
A. .50
B. .25
C. .35
D. .65
Q13. What is the probability of NOT getting two outs in a row?
A. .30
B. .91
C. .88
D. .09
Q14. A pie chart is typically most useful for the ______ level of measurement.
A. Nominal
B. Ordinal
C. Interval
D. Ratio
Q15. In regression, the sum of all deviations (not squared) from the mean is equal to:
A. The mean
B. The variance
C. Zero
D. The median
Use the following information to answer questions 16-18: You know from the MU registrar that GPAs of MU students are normally distributed with μ = 2.95 and σ = .6.
Q16. How many standard deviations from the mean is Sophia, with a GPA of 3.5?
A. 0.92
B. 1.33
C. -1.25
D. 3.00
Q17. What percent of students have a GPA of 2.5 or above?
A. 22.66
B. 12.93
C. 77.34
D. 27.89
Q18. What percent of students have a GPA less than 2.0?
A. 1.58%
B. 23.00%
C. 77.65%
D. 5.71%
Q19. Bicycles arrive at a bike shop as parts in a box. Before they can be sold, they must be unpacked and assembled. Based on past experience, the bike shop owner knows that assembly times follow (roughly) a Normal distribution with a mean of 25 minutes and a standard deviation of 3 minutes. A customer walks into the bike shop and wishes to buy a bike like the one in the window, but in a different color. The shop has one, but it is still in the box, so it will need to be assembled. What is the probability that the bike will be ready within a half hour?
A. .0478
B. .1587
C. .8413
D. .9525