Quiz 3

Question 1

Which of the following is a true experimental design?

Select one:

a. one group posttest only
b. posttest only with non-equivalent control group
c. one group pretest-posttest
d. two conditions, tested within subjects

Answer 1

d. two conditions, tested within subjects

Question 2

The two basic elements of a true experimental design are:

Select one:

a. a control group and random allocation of subjects to conditions.
b. a control group or a control condition and random allocation of subjects to groups.
c. random selection of subjects and random allocation of subjects to conditions.
d. random selection of subjects and each subject experiences every condition.

Answer 2

b. a control group or a control condition and random allocation of subjects to groups.

Question 3

Which one of the following procedures is an appropriate way to control for order effects in a within-subjects experiment? Arrange so that each condition:

Select one:

a. follows every other condition an equal number of times.
b. occurs equally often in each ordinal position.
c. is presented once to each group.
d. occurs only once.

Answer 3

b. occurs equally often in each ordinal position.

Question 4

In a 2 x 3 between-subjects factorial experiment, each subject serves in _________ condition(s) out of _________ conditions in the experiment.

Select one:

a. 1; 5
b. 1; 6
c. 2; 3
d. 5; 6

Answer 4

b. 1; 6

Question 5

In a line graph of results of a 2 x 2 factorial experiment, an interaction is shown by:

Select one:

a. some points higher than others.
b. one line higher than another.
c. two lines not parallel to the x axis.
d. two lines not parallel to each other.

Answer 5

d. two lines not parallel to each other.

Question 6

In a mixed design,

Select one:

a. there is one independent variable and one dependent variable.
b. one independent variable is manipulated and the other independent variable(s) is(are) not manipulated.
c. at least one independent variable is tested within-subjects and the other independent variable(s) is(are) tested between-subjects.
d. the number of independent variables and the number of dependent variables are different.

Answer 6

c. at least one independent variable is tested within-subjects and the other independent variable(s) is(are) tested between-subjects.

Question 7

An automobile plant plans to implement a new assembly procedure throughout the plant in order to increase productivity. To find out whether the new procedure is better than the old procedure, management plans to compare weekly productivity over the last six months before the change with the first six months after the change. What type of quasi-experimental design is illustrated in this example?

Select one:

a. interrupted time-series
b. delayed control group
c. cross-sequential
d. repeated treatment

Answer 7

a. interrupted time-series

Question 8

Discuss the advantages and disadvantages of between-subjects and within-subjects experimental designs. (2 points)

Answer 8

Advantages of within subjects design:

• they require fewer participants than between-subjects designs.
• it is easier to control for confounding variables since we are using the same subjects to test multiple conditions, so as an example, IQ will not have a confounding effect on an experiment that measures memory since a within subject design eliminates the variance of IQ

Disadvantages of within subject design:

• order and sequence effects play a big role and are sometimes hard to eliminate entirely
• these effects can sometimes be remedied through counterbalancing measures

Advantages of between subjects design:

• can test multiple conditions simultaneously thus saving a lot of time
• do not have to worry about order or sequence effects since each participant experiences only one condition

Disadvantages of between subject design:

• require many more people to run several treatments at the same time, thus are more complex and difficult to administer
• more expensive to run a larger study
• more chance of encountering confounding variables since with each new person added we are adding unaccounted for factors that may be contributing to the results