Deck 9: Experimental Designs: Within-Subjects Design

Question 1

In studies with a group of individuals being tested in a series of treatment conditions, factors such as history, instrumentation, and maturation threaten ____.

A) internal validity only
B) external validity only
C) both internal and external validity
D) neither internal nor external validity

Answer 1

A

Question 2

Which research design involves measuring the same group of participants in two different treatment conditions?

A) Between-subjects
B) Within-subjects
C) Matched subjects
D) A combined, two-factor design

Answer 2

B

Question 3

In a within-subjects study that extends over a relatively long time, it is possible that there will be systematic changes in the participants' skills or knowledge during the time of the study. When these changes influence the participants' scores, causing scores at the end of the study to be different from scores at the beginning, the effect is called ____.

A) history effects
B) instrumentation
C) maturation
D) regression toward the mean

Answer 3

C

Question 4

What is a time-related threat to internal validity for a within-subjects experiment?

A) Carry-over
B) Instrumentation
C) Progressive error
D) Assignment bias

Question 5

During the first treatment condition of a within-subjects experiment, the participants learn a new skill that helps improve their performance in later treatment conditions. For this study, the internal validity is threatened by ____.

A) history effects
B) instrumentation
C) order effects
D) regression toward the mean

Question 6

The tendency for individuals who have extreme scores (high or low) on one measurement and to have less extreme scores on a second measurement is called ____.

A) history
B) instrumentation
C) maturation
D) regression toward the mean

Question 7

What are the two major threats to internal validity in within-subjects experiments?

A) Individual differences and variance
B) Individual differences and environmental variables
C) Time-related variables and individual differences
D) Environmental variables and time-related variables

Question 8

History, maturation, and instrumentation are especially threatening to studies when _____.

A) order effects also exist
B) environmental variables are minimal
C) the series of treatments extends over a long period of time
D) there are big individual differences between participants

Question 9

For an experiment comparing two treatment conditions, there will be ____ score(s) for each participant if a within-subjects design is used and there will be ____ score(s) for each participant if a between-subjects design is used.

A) one; one
B) one; two
C) two; one
D) two; two

Question 10

A researcher is evaluating the changes in performance that occur during a six-week training program. Participants are observed at the beginning and at the end of the program and the researcher rates each individual's level of performance. When the researcher's standards for rating performance change from the first observation to the last, then the internal validity of the study is threatened by ____.

A) history
B) instrumentation
C) maturation
D) statistical regression

Question 11

Dr. Mias is conducting a study on the effect of meditation on the anxiety levels of elderly hospice patients; however, the patients' declining health affects their anxiety levels in between each measurement. Which threat to internal validity has confounded this study?

A) History
B) Instrumentation
C) Maturation
D) Regression toward the mean

Question 12

A group of college students is participating in a memory study that involves performing the same task each day under different circumstances; however, as each day goes by, the students are obviously getting more comfortable with completing the task. Which threat to internal validity has confounded this study?

A) History
B) Selection bias
C) Practice
D) Fatigue

Question 13

How many participants would be needed for a within-subjects experiment comparing four different treatment conditions with a total of 20 scores in each treatment?

A) 20
B) 40
C) 80
D) Anywhere from 20 to 80

Question 14

A researcher should increase the time between treatment conditions in a within-subjects experiment when he or she wants to decrease the threat of _____.

A) history
B) fatigue
C) maturation
D) instrumentation

Question 15

Order effects include ____.

A) history and instrumentation effects
B) carryover and progressive error effects
C) maturation and regression effects
D) assignment bias and selection bias

Question 16

In a within-subjects research study, factors that change over time, such as history and maturation, can be threats to ____.

A) internal validity only
B) external validity only
C) both internal and external validity
D) neither internal nor external validity

Question 17

When one treatment condition has a lasting effect on individuals and influences their scores in future treatments, the study is confounded by ____.

A) history
B) instrumentation
C) carry-over effects
D) progressive error

Question 18

Dr. Feliciano is conducting a study of sleep on children's activity level that takes place over several days; however, Halloween falls in the middle of his study, and he notices that on Halloween, the children are especially active during his observation. Which threat to internal validity has confounded this study?

A) Subject selection bias
B) Volunteerism
C) Fatigue
D) History

Question 19

Order effects can become a confounding variable because ____.

A) all the treatment conditions are affected equally
B) earlier conditions affect outcomes under later conditions
C) other time-related threats such as history become indistinguishable
D) individual differences between treatment conditions are created

Question 20

When one treatment condition has a lasting effect on the participants and influences their scores in later treatments, the study is confounded by ____.

A) history effects
B) instrumentation
C) carryover effects
D) progressive error

Question 21

What is an advantage of the between-subjects design versus the within-subjects design?

A) It generally requires fewer participants.
B) It usually is a more sensitive test (more likely to detect a treatment effect).
C) It eliminates the risk of order effects.
D) It eliminates potential problems that may be caused by individual differences.

Question 22

What does counterbalancing involve?

A) Matching the treatment conditions with respect to time
B) Keeping the time between measurements constant
C) Selecting two groups of identical participants
D) Holding the order of the treatment conditions constant for all participants

Question 23

Which manipulation of the time period between treatment conditions reduces the chances of history influencing the results of a within-subjects experiment?

A) Shortening
B) Lengthening
C) Shortening and then lengthening
D) Randomly varying the period

Question 24

What is a big advantage of using a multiple-treatment design?

A) The data can provide more in-depth information about the relationship between the independent and dependent variables.
B) It becomes dramatically easier to see the statistical significance of differences between treatments.
C) It usually takes less time, thereby lowering the rate of participant attrition.
D) It becomes easier to counterbalance a design as the number of treatment conditions increases.

Question 25

A researcher would like to conduct an experiment, but is concerned about strong order effects. One solution is to use a ____.

A) within-subjects design
B) between-subjects design
C) correlational design
D) descriptive strategy

Question 26

Compared to a between-subjects design, the variance in a within-subjects design is greatly reduced because the ____ are measured and statistically removed.

A) individual differences
B) carry over effects
C) progressive error effects
D) instrumentation effects

Question 27

A matched-subjects design attempts to eliminate the problems associated with ____ that are a concern for between-subjects designs and also eliminate the problems associated with ____ that are a concern for within-subjects designs.

A) order effects; order effects
B) order effects; individual differences
C) individual differences; individual differences
D) individual differences; order effects

Question 28

In a Latin square, ____.

A) each participant receives each treatment in the same order
B) each treatment is administered first in the series for one group of participants
C) each participant receives a completely different treatment
D) every possible ordering of treatment conditions is used

Question 29

For a within-subjects study comparing two treatments, A and B, a researcher expects that practice in the first treatment will improve the participants' scores in the second treatment. If the order of treatments is counterbalanced, then the practice will ____.

A) influence scores in treatment A, but not in treatment B
B) influence scores in treatment B, but not in treatment A
C) influence scores in treatment A for half the participants and scores in treatment B for half the participants
D) not influence the scores in either treatment condition because the treatments are counterbalanced

Question 30

How many groups of participants would be needed to partially counterbalance four treatment conditions?

A) 4
B) 8
C) 16
D) 24

Question 31

A Latin square is used with _____.

A) partial counterbalancing
B) complete counterbalancing
C) matched-subjects designs
D) all within-subjects designs

Question 32

For an experiment that compares two treatment conditions with ten scores in each treatment, which design would require the smallest number of participants?

A) Between participants
B) Within participants
C) Matched subjects
D) All designs would require the same number of participants.

Question 33

A Latin square design is used to determine the order of treatments that will be used in a within-subjects experiment comparing five treatments labeled A, B, C, D, and E. How many groups of participants will receive treatment E as the first treatment?

A) 0
B) 1
C) 5
D) Cannot answer without more information

Question 34

What is the effect of counterbalancing?

A) It eliminates order effects.
B) It spreads order effects evenly across the treatment conditions.
C) It eliminates individual differences.
D) It spreads individual differences evenly across treatment conditions.

Question 35

The most appropriate hypothesis test for a within-subjects design that compares three treatment conditions is a(n) ____.

A) an independent-measures t -test
B) a repeated-measures t -test
C) a repeated-measures analysis of variance
D) a chi-square test for independence

Question 36

Within-subjects designs are most useful when individual differences are ____.

A) large and there are many participants available
B) large and there are relatively few participants available
C) small and there are many participants available
D) small and there are relatively few participants available

Question 37

At a minimum, how many participants would be needed for a matched-subjects design comparing three different treatment conditions with 20 scores in each treatment?

A) 20
B) 60
C) 90
D) 120

Question 38

In a within-subjects experiment comparing two treatments, the researcher is concerned that the results may be confounded by outside events that occur between the first and second treatments. One way to reduce the likelihood that internal validity will be influenced by an outside event is to ____.

A) switch to a between-subjects design
B) increase the amount of time between the two treatments
C) switch the order of treatments
D) decrease the intensity of the treatment

Question 39

In a completely counterbalanced within-subjects experiment, ____.

A) each group receives a different treatment
B) each participant receives each treatment in the same order
C) a series of treatments is presented in every possible sequence
D) participants receive a random order of treatment conditions

Question 40

A way to control for order effects in a within-subjects experiment is to use ____.

A) matching
B) randomization
C) holding order constant
D) counterbalancing

Question 41

The tendency for extremely high scores on one measurement to be followed by lower scores on a second measurement is called statistical regression.

Question 42

One disadvantage of within-subject designs is that they tend to require more participants than are needed for between-subject designs.

Question 43

For a within-subjects experiment with data measured on an interval or ratio scale, researchers typically compute a mean score for each treatment condition.

Question 44

Counterbalancing effectively eliminates order effects.

Question 45

Partial counterbalancing for four treatments would require four groups of participants.

Question 46

One general concern for within-subjects research is that participation in one treatment condition may influence an individual's scores in a later treatment condition. This creates a threat to internal validity known as order effects.

Question 47

Counterbalancing involves having different groups of participants move through the series of treatments in different orders.

Question 48

A matched-subjects design attempts to gain the advantages of a within-subjects design, although it actually compares different groups of participants.

Question 49

If one or more of the treatments in an experiment is expected to have a large and long-lasting effect that could influence the participants' scores in later treatments, the best strategy is to use a between-subjects design.

Question 50

The larger the number of treatment conditions, the easier it is to completely counterbalance them.

Question 51

If the measurement device changes during the course of a within-subjects study so that the participants' scores are influenced, internal validity is threatened by statistical regression.

Question 52

It is impossible to have order effects with a between-subjects design.

Question 53

Random assignment is used to control order effects in a within-subjects experiment.

Question 54

To completely counterbalance a study, each possible order of treatments must be presented to a participant.

Question 55

Randomly assigning participants to treatment conditions is not a part of within-subjects experiments.

Question 56

A within-subjects design would be appropriate for a research study that compares problem-solving ability for participants with three different levels of self-esteem (high self-esteem, medium self-esteem, and low self-esteem).

Question 57

The advantages of within-subjects designs solve the disadvantages of between-subjects designs and vice versa.

Question 58

A problem with counterbalancing is that it can increase variance in the data by adding order effects to some individuals but not others.

Question 59

For a within-subjects experiment, one advantage of a two-treatment design compared to a multiple-treatment design is that it is easier to counterbalance.

Question 60

Using a Latin square to counterbalance a within-subjects experiment ensures that every possible ordering of treatment conditions is used.

Question 61

Outline the major advantages and disadvantages of using a two-treatment design and a multiple-treatment design.

Question 62

Provide an example of order effects in a within-subjects research study and explain why order effects are a concern for researchers.

Question 63

Identify two time-related factors that can threaten the internal validity of a within-subjects research study. In each case, explain how the factor could be a confounding variable.

Question 64

Describe the process of counterbalancing and explain how this process reduces the risk of problems from order effects.

Question 65

Describe a matched-subjects design and explain how this design attempts to avoid the major problems that exist with a between-subject design and a within-subjects design.

Question 66

Explain what partial counterbalancing is and when it would be used in a within-subjects study.

Question 67

Under what circumstances is a within-subjects design NOT a good choice for a research study?