Chapter 8 Experimental Designs Between Subjects Design.docx.pdf
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1. A design that compares different groups of scores obtained from separate groups of participants is a ____ design. a. single-subjects b. betweensubjects c. within-subject d. matched groups ANSWER: b DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 2. An experiment that uses a different group of participants for each treatment condition is called a ____ design. a. single-subjects b. betweensubjects c. within-subject d. matched groups ANSWER: b DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 3. A between-subjects design differs from a within-subjects design in that in a between-subjects design, ____. a. only one group of participants is used b. only variables “between” the participants are examined c. there is a different group of participants for each treatment conditions d. each participant is exposed to each level of the independent variable ANSWER: c DIFFICULTY: Difficult REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Analysis 4. In an experiment examining the effects of size of plate on amount of food eaten, one group of participants is measured after eating food on 12 inch plates. A week later, the same group of participants is measured after eating food on 10 inch plates. This is an example of a ____ design. a. single-subjects b. betweensubjects c. within-subjects d. matched groups ANSWER: c DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Apply 5. In an experiment examining the effects of size of plate on amount of food eaten, one group of participants is measured after eating food on 12-inch plates. Another group of participants is measured after eating food on 10-inch plates. This is an example of a ____ design. a. single-subjects b. betweensubjects c. within-subjects d. matched groups ANSWER: b DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Apply 6. Which statement best characterizes a between-subjects experimental design? a. Participants are randomly selected from two different populations. b. Each participant is assigned to one condition of the experiment. c. Each participant is assigned to every condition of the experiment. d. Participants are assigned to a random number of conditions. ANSWER: b DIFFICULTY: Difficult REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Analysis 7. In a between-subjects design, ____. a. only one score is obtained for each participant b. at least two scores are obtained for each participant c. one score is d. obtained for each treatment condition for each participant e. each score represents multiple participants ANSWER: a DIFFICULTY: Difficult REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 8. A between-subjects experiment comparing four treatment conditions produces 20 scores in each treatment condition. How many scores were obtained for each participant? a. 1 b. 4 c. 20 d. 80 ANSWER: a DIFFICULTY: Difficult REFERENCES 8.1 Introduction to Between-Subjects Experiments8.1 Introduction to Between: Subjects Experiments LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Apply 9. A between-subjects experiment comparing four treatment conditions produces 20 scores in each treatment condition. How many individuals participated in the entire experiment? a. 1 b. 4 c. 20 d. 80 ANSWER: d DIFFICULTY: Difficult REFERENCES: 8.1 Introduction to Between-Subjects Experiments LEARNING OB GRAV.METH.16.08.02 - Explain the general advantages and disadvantages of JECTIVES: between-subjects design compared to within-subjects design. KEYWORDS: Bloom’s: Apply 10. If a between-subjects experiment produces 50 scores in treatment 1 and 50 scores in treatment 2, then the experiment must have employed ____. a. 25 participants b. 50 participants c. 100 participants d. 200 participants ANSWER: c DIFFICULTY: Difficult REFERENCES: 8.1 Introduction to Between-Subjects Experiments LEARNING OB GRAV.METH.16.08.02 - Explain the general advantages and disadvantages of JECTIVES: between-subjects design compared to within-subjects design. KEYWORDS: Bloom’s: Apply 11. An advantage of a between-subject design is that ____. a. scores are influenced by practice effects b. scores are influenced by fatigue c. each score is independent of all the other scores d. they require large numbers of participants ANSWER: c DIFFICULTY: Difficult REFERENCES: 8.1 Introduction to Between-Subjects Experiments LEARNING OB GRAV.METH.16.08.02 - Explain the general advantages and disadvantages of JECTIVES: between-subjects design compared to within-subjects design. KEYWORDS: Bloom’s: Analysis 12. Compared to within-subjects designs, between-subjects designs require relatively ____. a. larger numbers of participants b. smaller numbers of participants c. less control of individual difference d. more concern for practice effects ANSWER: a DIFFICULTY: Moderate REFERENCES: 8.1 Introduction to Between-Subjects Experiments LEARNING OB GRAV.METH.16.08.02 - Explain the general advantages and disadvantages of JECTIVES: between-subjects design compared to within-subjects design. KEYWORDS: Bloom’s: Anaysis 13. In a between-subjects experiment, when the process of assigning participants to the treatment conditions produces groups with different characteristics, the ____of the study is threatened. a. internal validity b. external validity c. reliability d. accuracy ANSWER: a DIFFICULTY: Difficult REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Analysis 14. When ____ occurs in a between-subjects experiment, it is impossible to determine whether differences between groups are caused by the treatments or by participant characteristics. a. fatigue b. practice c. assignment bias d. resentful demoralization ANSWER: c DIFFICULTY: Difficult REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Analysis 15. In a between-subjects design, the separate groups must be as ____. a. similar in participant characteristics as possible b. different in all environmental variables as possible c. similar in treatment conditions as possible d. similar on the dependent variable measures as possible. ANSWER: a DIFFICULTY: Difficult REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Analysis 16. Why is random assignment used in between-subjects experimental designs? a. to hold participant characteristics constant b. to ensure a nonbiased sample c. to ensure anonymity of the research participants d. to eliminate systematic differences between the groups ANSWER: d DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Analysis 17. Because random assignment is likely to create groups of different sizes, researchers often employ ____. a. restricted random assignment b. matched random assignment c. simple random assignment d. sampling ANSWER: a DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Understand 18. An advantage of holding a variable constant rather than using random assignment to form your groups is that holding a variable constant ____. a. reduces error due to participant differences b. is easier than randomization c. prevents confounding d. ensures a nonbiased sample ANSWER: c DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Analysis 19. Which approach is most effective in preventing confounding by participant characteristics? a. matching the characteristics across treatments b. randomizing the variable across treatment c. including a no-treatment control group d. having a placebo control group ANSWER: b DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Analysis 20. A limitation of using matching rather than random assignment to form groups in a between-subjects experiment is that matching ____. a. requires another level of work b. increases error due to participant differences c. requires at least twice as many participants d. increases the need for control groups ANSWER: a DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Analysis 21. Holding a participant characteristic (such as age or gender) constant strengthens ____ and weakens ____. a. internal validity; external validity b. external validity; internal validity c. reliability; validity d. accuracy; reliability ANSWER: a DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Analysis 22. Holding a variable constant prevents a participant characteristic from becoming a confound by ____. a. eliminating variability in that characteristic b. reducing error c. ensuring a nonbiased sample d. increasing the differences between the groups ANSWER: a DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Analysis 23. In a between-subjects design, individual differences (participant variables) are a problem because they can ____. a. become confounding variables b. decrease variability of the scores c. preclude the use of statistical analyses d. produce fatigue effects ANSWER: a DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Understand 24. In a between-subjects design, large individual differences can produce ____. a. large between-treatment differences, making it easier to see real treatment effects b. small within-treatment variance, making it easier to see real treatment effects c. large within-treatment variance, making it difficult to see real treatment effects d. small between-treatment difference, making it difficult to see real treatment effects ANSWER: c DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Analysis 25. Researchers typically try to ____. a. increase the differences between treatments and decrease the variance within treatments b. decrease the differences between treatments and increase the variance within treatments c. increase the differences between treatments and increase the variance within treatments d. decrease the differences between treatments and decrease the variance within treatments ANSWER: a DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Analysis 26. Increasing variance within groups ____ the likelihood of finding a difference between the treatment conditions. a. increases b. decreases c. does not affect d. increase, then decreases ANSWER: b DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Analysis 27. Standardizing procedures, standardizing treatment settings, and limiting individual differences all have the effect of ____. a. reducing variance between treatments b. increasing variance within treatments c. increasing variance between treatments d. reducing variance within treatments ANSWER: d DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 28. In a between-subjects design, holding constant a participant characteristic, such as age or gender, is one way to ____. a. reduce the variance within treatments b. maximize the variance within treatments c. increase individual differences. d. increase sample size ANSWER: a DIFFICULTY: Moderate REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 29. Limiting individual differences is a way to ____. a. standardize procedures b. standardize treatment settings c. reduce the variance within treatments d. maximize the variance within treatments ANSWER: c DIFFICULTY: Moderate REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 30. Which has the effect of reducing variance? a. random assignment b. matched assignment c. holding variables constant d. random selection ANSWER: c DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Analysis 31. Compensatory equalization occurs when ____. a. an untreated group learns of the treatment received by another group and then works extra hard to show that they can perform just as well as individuals receiving the treatment b.an untreated group learns of the treatment received by another group and then demands the same treatment c. an untreated group learns of the treatment received by another group and then becomes less motivated d.participants withdraw from a research study before it is completed ANSWER: b DIFFICULTY: Moderate REFERENCES 8.5 Other Threats to Internal Validity of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.07 - Describe how differential attrition and communication BJECTIVES: between participants can threaten the internal validity of between-subjects designs and identify these problems when they appear in a research study. KEYWORDS: Bloom’s: Understand 32. What is one risk in a study, whether or not participants in different groups are able to communicate with each other? a. resentful demoralization b. compensatory equalization c. diffusion d. differential attrition ANSWER: DIFFICULTY: REFERENCES : LEARNING O BJECTIVES: d Moderate 8.5 Other Threats to Internal Validity of Between-Subjects Designs GRAV.METH.16.08.07 - Describe how differential attrition and communication between participants can threaten the internal validity of between-subjects designs and identify these problems when they appear in a research study. KEYWORDS: Bloom’s: Analyze 33. Differential attrition refers to ____. a. differences in one group of participants from another group b. differences in the number of withdrawals among experimental groups c. the spreading of treatment effects from the experimental to the control group d. the demands of the untreated group to receive equal treatment ANSWER: b DIFFICULTY: Easy REFERENCES 8.5 Other Threats to Internal Validity of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.07 - Describe how differential attrition and communication BJECTIVES: between participants can threaten the internal validity of between-subjects designs and identify these problems when they appear in a research study. KEYWORDS: Bloom’s: Understand 34. The single-factor two-group design includes ____. a. only two levels of one independent variable b. a treatment and a control group c. two dependent variables d. multiple treatment and control groups ANSWER: a DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 35. What is the most common statistical analysis for a single-factor two-group design? a. ANOVA b. independent-measures t test c. repeated-measures t test d. regression ANSWER: b DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 36. What is the most common statistical analysis for a single-factor multiple-group design? a. ANOVA b. independent-measures t test c. repeated-measures t test d. regression ANSWER: a DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 37. When comparing means in a two-group design, which statistical analysis is most appropriate? a. independent-measures t test b. repeated-measures t test c. single-factor analysis of variance d. chi-square test for independence ANSWER: a DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 38. The primary limitation of a two-group design is that it ____. a. is extremely difficult to interpret b. decreases the chances of demonstrating a significant mean difference c. tends to reduce the differences between the groups d. may not provide a complete picture of the relationship between the variables ANSWER: d DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 39. When comparing means in a single-factor multiple group design, which statistical analysis is most appropriate? a. independent-measures t test b. repeated-measures t test c. single-factor analysis of variance d. chi-square test for independence ANSWER: c DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 40. A limitation of a single-factor multiple group design is that the ____. a. mean differences between the groups become smaller as more groups are used b. interpretation is too simplistic c. chances of demonstrating a significant mean difference are increased d. complete picture of the relationship between the variables cannot be seen ANSWER: a DIFFICULTY: Moderate REFERENCES 8.6 Applications and Statistical Analyses of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.08 - Describe how between-subjects designs are used to BJECTIVES: compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 41. A between-subjects experiment comparing three treatments requires three separate groups of participants. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 42. One characteristic of a between-subjects design is that the data consist of exactly one score for each participant. a. True b. Fals e ANSWER: DIFFICULTY: REFERENCES : LEARNING O BJECTIVES: True Moderate 8.1 Introduction to Between-Subjects Experiments GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 43. A between-subjects experiment with 25 scores in treatment I and 25 scores in treatment II must have a total of 25 participants in the experiment. a. True b. Fals e ANSWER: False DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 44. One advantage of a between-subjects design is that each score is completely independent of the other scores in the data. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES: 8.1 Introduction to Between-Subjects Experiments LEARNING OB GRAV.METH.16.08.02 - Explain the general advantages and disadvantages of JECTIVES: between-subjects design compared to within-subjects design. KEYWORDS: Bloom’s: Understand 45. An advantage of between-subjects designs is that they require fewer participants than are typically needed for withinsubjects designs. a. True b. Fals e ANSWER: False DIFFICULTY: Difficult REFERENCES: 8.1 Introduction to Between-Subjects Experiments LEARNING OB GRAV.METH.16.08.02 - Explain the general advantages and disadvantages of JECTIVES: between-subjects design compared to within-subjects design. KEYWORDS: Bloom’s: Analysis 46. In a between-subjects experimental design, individual differences can become a confounding variable. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Understand 47. In a between-subjects experiment, if the participants in one group are noticeably older than the participants in another group, then participant age is a confounding variable and threatens the internal validity of the experiment. a. True b. Fals e ANSWER: True DIFFICULTY: Difficult REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Apply 48. Assignment bias can threaten the internal validity of between-subjects experiments. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Understand 49. Random assignment guarantees that participant characteristics do not become a confounding variable. a. True b. Fals e ANSWER: False DIFFICULTY: Difficult REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Understand 50. In a between-subjects experiment, increasing the variance within treatments increases the likelihood of finding significant differences between treatments. a. True b. Fals e ANSWER: False DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Understand 51. In a between-subjects experiment, one way to reduce the variance within treatments is to create more homogeneous groups by holding constant a participant characteristic such as age or gender. a. True b. Fals e ANSWER: True DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Understand 52. For a between-subjects experiment, any factor that increases the variance within treatments also increases the likelihood of finding a significant difference between treatments. a. True b. Fals e ANSWER: False DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.05 - Describe how individual differences influence BJECTIVES: variability, both between-treatment differences and within-treatments variance, and explain how variance within treatments can influence the interpretation of research results. KEYWORDS: Bloom’s: Analysis 53. A disadvantage of holding a variable constant is that it limits an experiment’s external validity. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 54. Holding a variable constant guarantees that the variable cannot become a confounding variable. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 55. Matching a variable across treatment guarantees that the variable cannot become a confounding variable. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 56. Randomizing a variable across treatments guarantees that the variable cannot become a confounding variable. a. True b. Fals e ANSWER: False DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 57. Holding a participant variable constant has the double advantage of (1) preventing the variable from becoming a confounding variable, and (2) reducing variance within groups. a. True b. Fals e ANSWER: True DIFFICULTY: Difficult REFERENCES 8.4 Individual Differences and Variability : LEARNING O GRAV.METH.16.08.06 - Identify the options for reducing or controlling the BJECTIVES: variance within treatment condition and explain how each option works. KEYWORDS: Bloom’s: Understand 58. Differential attrition can threaten the internal validity of a between-subjects experiment. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.5 Other Threats to Internal Validity of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.07 - Describe how differential attrition and communication BJECTIVES: between participants can threaten the internal validity of between-subjects designs and identify these problems when they appear in a research study. KEYWORDS: Bloom’s: Understand 59. Validity is threatened in a between-subjects design when participants in one group have an opportunity to talk with participants in the other. a. True b. Fals e ANSWER: True DIFFICULTY: Moderate REFERENCES 8.5 Other Threats to Internal Validity of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.07 - Describe how differential attrition and communication BJECTIVES: between participants can threaten the internal validity of between-subjects designs and identify these problems when they appear in a research study. KEYWORDS: Bloom’s: Understand 60. In a between-subjects design, to compare proportions between groups, an independent-measures t test is appropriate. a. True b. Fals e ANSWER: False DIFFICULTY: REFERENCES : LEARNING O BJECTIVES: Difficult 8.6 Applications and Statistical Analyses of Between-Subjects Designs GRAV.METH.16.08.08 - Describe how between-subjects designs are used to compare means and proportions for two or more groups, identify the statistical techniques that are appropriate for each application, and explain each design’s strengths and weaknesses. KEYWORDS: Bloom’s: Understand 61. Describe the basic characteristics of a between-subjects experiment. ANSWER: In a between-subjects experiment different groups of individuals are compared. A researcher manipulates the independent variable to create different treatment conditions. Each participant is exposed to only one level of the independent variable. A different group of participants is used for each level of the independent variable. DIFFICULTY: Easy REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Understand 62. Explain the benefit of independent scores in a between-subjects design. ANSWER: In a between-subjects design, each participant is measured only once which means that each score is independent of the other scores. Thus, you can be confident that the participant’s score is not influenced by factors such as previous practice or fatigue or any lingering aftereffects from a previous treatment. DIFFICULTY: Moderate REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Evaluate 63. Describe why the assignment of subjects to the conditions of an experiment in a between-subjects design is such a critical issue. ANSWER: By assigning participants to conditions, a researcher can take steps to ensure that the different groups are equivalent before any treatments are administered. If the groups are equivalent before treatment but different after treatment, the researcher can be reasonably confident that the treatments are responsible for causing the differences. DIFFICULTY: Moderate REFERENCES 8.2 Individual Differences as Confounding Variables : LEARNING O GRAV.METH.16.08.03 - Define individual differences and explain how BJECTIVES: assignment bias and confounding from environmental variables can threaten the internal validity of a between-subjects design. KEYWORDS: Bloom’s: Evaluate 64. Describe the advantages and disadvantages of matching groups of participants in a between-subjects experiment. ANSWER: The advantage of matching groups of participants in a between-subjects experiment is that it is a relatively easy way to ensure that specific variables do not become confounding variables. The disadvantages of matching include: a) the measurement procedure adds another level of work to the study, b) it can be difficult to match groups on several different variables simultaneously, c) groups cannot be matched on every single variable that might differentiate participants. DIFFICULTY: Moderate REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Evaluate 65. Describe the advantages and disadvantages of holding a participant characteristic constant in a between-subjects experiment. ANSWER: The advantage of holding a variable constant in a between-subjects experiment is that it is an effective way to prevent a variable from confounding a research study. However, the disadvantage is that by preventing the natural range of variation, the external validity of the research is limited. DIFFICULTY: Moderate REFERENCES 8.3 Limiting Confounding by Individual Differences : LEARNING O GRAV.METH.16.08.04 - Identify the three primary techniques for limiting BJECTIVES: confounding by individual differences in between-subjects experiments (random assignment, matched assignment, and holding variables constant) and explain how each one works. KEYWORDS: Bloom’s: Evaluate 66. Create an example of a between-subjects experiment. Identify the independent and dependent variables and briefly describe the experiment. Indicate the number of levels of the independent variable and identify them. ANSWER: Student answers will vary but should all include a manipulated independent variable that creates two or more treatment conditions and a dependent variable that is measured in each treatment condition. To qualify as a between-subjects experiment, there must be a separate group of participants for each of the different treatment conditions. DIFFICULTY: Difficult REFERENCES 8.1 Introduction to Between-Subjects Experiments : LEARNING O GRAV.METH.16.08.01 - Describe the defining characteristics that differentiate a BJECTIVES: between-subjects design and a within-subjects design, and identify these designs when they appear in the literature. KEYWORDS: Bloom’s: Apply 67. Describe some of the problems that can develop if participants from different treatment conditions have an opportunity to talk with each other during the course of the experiment. ANSWER: If participants in a no-treatment condition talk with participants in a treatment condition they may learn about the treatment and adopt some of the treatment components. This leads to diffusion of treatment. If participants in an inferior condition learn about a superior treatment being received by others, they may demand equal treatment (compensatory equalization), they may become extra motivated to make up for the inferior treatment (compensatory rivalry), or they may give up in the face of a hopeless situation (resentful demoralization). DIFFICULTY: Moderate REFERENCES 8.5 Other Threats to Internal Validity of Between-Subjects Designs : LEARNING O GRAV.METH.16.08.07 - Describe how differential attrition and communication BJECTIVES: between participants can threaten the internal validity of between-subjects designs and identify these problems when they appear in a research study. KEYWORDS: Bloom’s: Evaluate
