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

Accepted Answer

A placebo control group is best suited to distinguish the effects of the treatment from effects due to client expectations, attention, and other nonspecific aspects. This type of control group involves administering a sham intervention that is not expected to have therapeutic effects but is designed to mimic the treatment in terms of the amount and type of attention given to participants. Participants in the placebo control group are not aware that they are receiving a sham intervention and are led to believe that they are receiving an actual treatment. By comparing the outcomes of the treatment group with those of the placebo control group, George can assess the specific effects of the treatment beyond the non-specific effects of attention and other factors.

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.

Accepted Answer

Factorial designs allow for the study of the effects of two or more independent variables on a dependent variable, including the interaction effects between these variables. However, as more variables are added, the design and interpretation of results become significantly more complex. This complexity can make it difficult to manage the study and analyze the data. Options B, C, and D are incorrect because factorial designs do allow for testing the interaction between independent variables, do not inherently increase unexplained variance with the addition of related independent variables, and there is no strict maximum number of independent variables that can be studied, although practicality and complexity may limit this.

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.

Accepted Answer

Kerlinger's MAXMINCON principle states that researchers should try to maximize the systematic variance of the variables under study and minimize error variance while controlling for extraneous variables. This description is best captured by choice D, which emphasizes minimizing error variance, maximizing systematic variance, and controlling extraneous variables.

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.

Accepted Answer

In a dependent sample design, the extraneous variables are already controlled for or eliminated through the design, so they do not need to be included as independent variables in the study.

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.

Accepted Answer

In a counterbalanced crossover design, participants are randomly assigned to different groups that vary in the treatment order. This means that each participant receives all treatments, but in a different order. This helps to control for potential order effects and increases the internal validity of the study.

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.

Accepted Answer

In a counterbalanced crossover design, each participant acts as their own control by participating in both conditions of the experiment, which can increase statistical efficiency and allow for the same statistical power with fewer participants compared to a between-subjects design where each participant is only exposed to one condition.

Question 7

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

Accepted Answer

A researcher may collect samples gradually throughout the investigation, or may even obtain samples from other researchers or sources.

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.

Accepted Answer

This is true. Factorial designs involve manipulating two or more independent variables and observing their effects on a dependent variable, while also examining possible interactions between the variables.

Question 9

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

Accepted Answer

Random assignment of participants to different treatment conditions is a defining feature of between-groups design, as it helps eliminate potential confounding variables and ensures that differences between groups are due to the treatment/manipulation being tested.

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.

Accepted Answer

A within-subjects experimental design involves each participant being exposed to all of the treatment conditions, allowing for a comparison of changes within the same individuals. Therefore, option C is the correct choice. Option A is describing a placebo-controlled experimental design. Option B is incorrect as a control group is not mandatory for within-subjects designs, as they serve as their control by being exposed to all conditions. Option D describes a between-subjects experimental design, where groups are compared rather than individuals across conditions.

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.

Accepted Answer

One strength of a pretest-posttest control group design is that pretests can be used to select and deselect participants before the actual treatment. This can help ensure that the groups are comparable in terms of the measured variable before the treatment. However, options B, C, and D are not strengths of this design. Option B is not necessarily true as confidentiality can be a concern regardless of the research design. Option C is not necessarily true as pretest-posttest designs can require a significant amount of work, particularly if multiple measures are used. Option D is not necessarily true as sensitizing effects can still occur, particularly if participants talk to each other or if there are other changes in the environment that occur between the pretest and posttest.

Question 12

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

Accepted Answer

In within-subjects designs, counterbalancing can be used to vary the order of treatments across participants to control for order effects, meaning not all participants receive treatments in the same sequence.

Question 13

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

Accepted Answer

Counterbalanced crossover designs ensure that each level of the independent variable is presented in each possible order, helping to minimize any potential order effects and increasing internal validity.

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

Accepted Answer

The posttest-only control group design is suitable for Yalda's study because it allows for random assignment of participants to groups and minimizes threats to internal validity (such as history and maturation) by not including a pretest or crossover design. Additionally, it is a practical option given the time and scope constraints of the study.

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.

Accepted Answer

In a posttest-only control group design, researchers have limited information about the equivalence of the groups before the treatment is administered. This can limit the ability to draw strong conclusions about the treatment effect.

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.

Accepted Answer

Participants in a placebo control group are given a fake treatment but are led to believe that it is as effective as the real treatment being given to the treatment group. This is done to account for any placebo effects and to ensure that any observed effects in the treatment group are not just due to the participants' belief in the effectiveness of the treatment.

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.

Accepted Answer

Participants placed in a matched control group are paired with participants in the treatment group to reduce variance. This is done to ensure that the treatment and control groups are similar in all respects except for the treatment being tested. Option A is incorrect as participants in a matched control group are not their own controls, they are compared to a control group that is matched to them. Option B is not necessarily true, as treatment may not be made available to the control group. Option C is not a desirable situation and goes against ethical considerations of informed consent and deception.

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.

Accepted Answer

In a crossover design, while one can observe the effects of different treatments on the dependent variable, attributing effectiveness solely based on the greatest change does not account for individual variability, potential carryover effects, or the possibility that the observed change might not directly translate to "effectiveness" in a broader or long-term context.

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.

Accepted Answer

In the posttest-only control group design, participants are only asked to provide responses at the posttest stage, making it easier to protect their confidentiality as compared to the pretest-posttest control group design where participants provide responses at both pretest and posttest stages.

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.

Accepted Answer

The answer of Which of the following is a weakness...

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

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

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

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.

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

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.

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

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

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

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

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

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

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

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

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.

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

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.

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.

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