Deck 11: True Experimental Designs: the Power of Between-Groups and Within-Subjects Designs

Question 1

George is conducting a research on the effectiveness of a new counseling technique in improving the career orientation of participants. Due to the availability of participants and the absence of cases where urgent treatment intervention was needed, there were no issues with the random assignment of participants to treatment groups. George wants to distinguish the effects of the treatment from effects due to client expectations, attention, and other nonspecific aspects. Which of the following control groups is best suited to his cause?

A) Waiting-list control group
B) Delayed-treatment control group
C) Placebo control group
D) Matched control group

Answer 1

C

Question 2

Which of the following is a weakness of the factorial design?

A) The study results become increasingly complex with the addition of more variables to the design.
B) The interaction of the independent variables with each other cannot be tested by this design.
C) Unexplained variance in the dependent variable is increased with the addition of related independent variables.
D) A maximum of five independent variables and their effects can be studied using this design.

Answer 2

A

Question 3

Which of the following describes the most essential rules of research as expressed by Kerlinger's MAXMINCON principle?

A) Researchers try to maximize error variance, minimize the systematic variance of the variables under study, and control extraneous variables.
B) Researchers try to maximize the systematic variance of the variables under study, minimize error variance, and control dependent variables.
C) Researchers try to maximize error variance, minimize the systematic variance of the variables under study, and control dependent variables.
D) Researchers try to maximize the systematic variance of the variables under study, minimize error variance, and control extraneous variables.

Answer 3

D

Question 4

In the context of dependent sample designs, all the extraneous variables should be included in the study as independent variables in order to determine their effects.

Question 5

Which of the following is true of a counterbalanced crossover design?

A) Participants are randomly assigned to different groups that vary in the treatment order.
B) Participants are given treatment after the conclusion of the posttest.
C) Participants are randomly assigned to different treatment conditions.
D) Participants are led to believe that a viable treatment is being rendered while it is actually ineffective.

Question 6

In general, a researcher can use half the number of participants in a counterbalanced crossover design and still retain the same statistical power as in the between-subjects design.

Question 7

A researcher must have an entire sample identified and available at the beginning of an investigation.

Question 8

Factorial designs are used when two or more independent variables are employed simultaneously to study their independent and interactive effects on a dependent variable.

Question 9

A major identifying feature of between-groups design is the random assignment of participants to different treatment conditions.

Question 10

Which of the following is a feature of a within-subjects experimental design?

A) Subjects are led to believe that a viable treatment is being rendered while it is actually ineffective.
B) The presence of a control group is mandatory for all experiments of this design.
C) Each participant is exposed to all of the treatment conditions.
D) Dependent variables are compared across two or more groups.

Question 11

Which of the following is a strength of a pretest-posttest control group design?

A) Pretests can be used to select and deselect participants before the actual treatment.
B) Confidentiality of the responses of the participants can be easily protected.
C) A considerable amount of the researcher's time and effort is saved.
D) Potential sensitizing effects pertaining to external validity can be eliminated.

Question 12

In all within-subjects designs, the order in which treatments are delivered is the same for all participants.

Question 13

Counterbalanced crossover designs help researchers control threats to internal validity due to order effects.

Question 14

Yalda is a research scholar in the Department of Psychology at University of Umbria. She wants to compare the effectiveness of moral education with that of threats of social and financial coercion as a deterrent to tendencies of cheating and corruption. She has resorted to random assignment of the participants to the groups to remove any systematic bias. But, neither Yalda nor the participants have the required amount of time or scope to delve into the treatment specific change of the dependent variable in each participant. She wants her study to have minimal unknown variances to the dependent variable. She does not want threats to internal validity such as history, maturation, order effects, and sequence effects to dilute the effectiveness of her findings. Which of the following research designs is suitable for her study?

A) Counterbalanced crossover design
B) Crossover design
C) Pretest-posttest control group design
D) Posttest-only control group design

Question 15

Which of the following is a weakness of a posttest-only control group design?

A) Researchers have limited information available about group equivalence prior to treatment.
B) It is expensive to the researcher in terms of time and effort.
C) Confidentiality of the responses is compromised as the participants are unable to respond anonymously.
D) Repeated testing may be occasionally bothersome to some participants.

Question 16

Participants in a placebo control group are led to believe that the treatment they are receiving is as effective as that being received by the real control group.

Question 17

Which of the following is true of participants placed in a matched control group?

A) The participants serve as their own control to minimize error variance caused due to imperfect matching.
B) Treatment is made available to the participants after the posttests after careful ethical consideration.
C) The participants are led to believe that a viable treatment is being rendered even if it is actually ineffective.
D) The participants are paired with participants in the treatment group to reduce variance.

Question 18

A researcher using a crossover design can safely conclude that the treatment which produces the greatest change in the value of the dependent variable is the most effective of the ones being studied.

Question 19

Among the two types of between-groups designs, it is easier to protect the confidentiality of responses of the participants in the posttest-only control group design.

Question 20

Which of the following is a weakness of within-subjects design?

A) Error variance due to normal individual variability tends to be high.
B) It is more time consuming when compared to a between-groups design.
C) Statistical power tends to decrease unless the number of participants are doubled.
D) Order effects can't be controlled and tend to confound results.