The library advisory committee at BK wants to know what percentage of

current students would like to borrow physical material (books, dissertations, microfilms etc.)

from other non-BK libraries and universities. They surveyed a sample of 200 BK students using

e-mails and found that 180 would like to borrow from other non-BK libraries and universities. In

this study, the population of interest is

a) the 200 students who were surveyed

b) all current BK students

c) all students in NY who would like to borrow from non-BK libraries and universities

d) the 180 students who would like to borrow from other non-BK libraries and universities

2. [2 points] Which is NOT one of the four fundamental principles in designing experiments?

a) Controlling

b) Randomization

c) Treatment

d) Replication

3. [2 points] Let X be a Poisson random variable with mean = 4 . What is the standard deviation of

the random variable 3X ?

a) 36

b) 18

c) 6

d) 12

4. [2 points] Which of the following plots is the most effective to look for potential skewness in the income

distribution of US citizens?

a) scatterplot

b) boxplot

c) histogram

d) barplot

Let A and B be independent events. Which of the following must be true?

a) P(A B) = 0

b) P(A B) = P(A) + P(B)

c) P(A) = P(A|B)

d) P(A) = P(B|A)

True or False? For each of the following questions, please answer either True or False . While justification

is not required, it is encouraged and may allow in some cases for partial credit to be awarded.

6. [2 points] A sampling strategy falls under the category of probability sampling if every unit in the

population has a positive probability of getting selected in the sample.

7. [1 points] Eye color is an example of ordinal variable.

8. [2 points] Two events are considered independent if their intersection is empty.

9. [2 points] In the presence of extreme outliers in data, interquartile range is often considered a more

appropriate measure of dispersion than standard deviation.

10. [2 points] The calculation V ar(X + X) = V ar(X) + V ar(X) = 2V ar(X) is correct.