CORRECT Answers
A school psychologist wants to test the effectiveness of a new method of teaching
English. She recruits 100 second-grade students and randomly divides them into two groups. Group 1 is
taught by means of the new method, while group 2 is taught by traditional methods. The same teacher
is assigned to teach both groups. At the end of the year, an achievement test is administered and the
results of the two groups are compared. (a) What is the response variable in this experiment? (b) Is the
response variable qualitative or quantitative? (c) Which of the following explanatory variables is
manipulated? (d) What are the treatments? How many treatments are there? (e) How are the factors
that are not controlled dealt with? (f) Which group serves as the control group? (g) What type of
,experimental design is this? (h) Identify the subjects. (i) Draw a diagram to illustrate the design. -
CORRECT ANSWER a. The scores on the achievement tests of both group 1 and group 2
b. The response variable is quantitative because it is a measurement
c. Method of teaching
d. The treatments are the new teaching method and the traditional teaching method. There are 2
treatments.
e. Random assignments
f. Group 2 serves as the control group because this group corresponds to the standard method that will
be compared to the other method
g. Completely randomized design
h. The 100 students
I. fig A random assignment - group A - New - Compare
Define the following term: (a) Experimental unit - CORRECT ANSWER A person, object, or some other
well defined item upon which a treatment is applied.
Consider the two questions shown below.
(a) What is the most important problem facing the nation?
(b) Would you be willing to pay for social media services if your user data was your personal property
that the media company could not sell?
, Will the order in which the questions are asked affect the survey results? If so, what can the pollster do
to alleviate this response bias?
Choose the correct CORRECT ANSWER er below. - CORRECT ANSWER D. No, there is no obvious
reason that question order would affect the survey results in this scenario.
What is a closed question? What is an open question?
A. A closed question has many correct CORRECT ANSWER ers, whereas an open question has only one
correct CORRECT ANSWER er.
B. A closed question is a free-response question, whereas an open question has fixed choices for
CORRECT ANSWER ers.
C. A closed question has fixed choices for CORRECT ANSWER ers, whereas an open question is a free-
response question.
D. A closed question always has yes or no CORRECT ANSWER ers, whereas an open question is a free-
response question. - CORRECT ANSWER C. A closed question has fixed choices for CORRECT ANSWER
ers, whereas an open question is a free-response question.
Discuss the advantages and disadvantages of each type of closed and open question: