Question 1

Dr.Dow Jones wants to know whether a problem-based approach to teaching economics will result in higher academic performance than his traditional method.Of the six sections of Economics 101 at his university,Dr.Jones randomly assigns three sections to the traditional method and three sections to the problem-based method for Unit 1 of the course.Then all sections switch instructional method for Unit 2.He plans to compare the performance of the two groups of sections on their Unit 1 and Unit 2 exams.The design of this study is:
A)within subjects (repeated measures)
B)quasi-experimental
C)true experimental
D)ex post facto

Accepted Answer

This study involves randomly assigning different sections of the same course to different instructional methods and then comparing their performance on exams. Since each section serves as its own control by switching instructional methods for Unit 2, this study is within subjects (repeated measures).

Question 2

Factorial designs allow researchers to study the effects of more than one independent variable simultaneously.Why is this advantageous? What information can factorial designs yield that nonfactorial designs cannot?

Accepted Answer

This is advantageous because researchers are often interested in more than one effect on the dependent variable.Oceanographers may want to study effects related to both water temperature and salinity.Child welfare workers may want to study the effects of family income,mother's education level,and history of abuse on coping ability.The factorial design not only allows researchers to study these various factors independently,but their interactions can be studied as well.Studying interactions allows researchers to investigate the extent to which two or more factors influence each other.Perhaps whales encounter health problems in warmer water only at certain levels of salinity.Perhaps parents cope more successfully with stress when both family income and/or education level surpass a certain threshold.Or perhaps family income influences coping ability only when there is no history of abuse.

Question 3

Penny Poodle wanted to know which dog obedience training program was more effective: Puppy Pride,the approach she has been using for any years,or Doggie Do-Right,a new approach.Penny convinced 50 human companions of untrained dogs to participate in her study.The dogs and their humans were randomly assigned to complete the Puppy Pride or Doggie Do-Right course.At the end of the training programs,all of the dogs were scored on their level of obedience on a standardized dog obedience checklist (scores could range from 10 to 100).The design of this study is:
A)one-shot experimental
B)ex post facto
C)posttest-only control-group design
D)within subjects

Accepted Answer

The study design described is a posttest-only control-group design, as there are two groups of dogs (Puppy Pride and Doggie Do-Right) and a control group is used to evaluate the effectiveness of the two training programs. The dogs are randomly assigned to the two groups, and their obedience is measured at the end of the training program on a standardized checklist. The other answer choices do not accurately describe the design of this study.

Question 4

As a secondary mathematics teacher,Hernandez conducted a study that explored whether giving children recess prior to testing helped their test performance.For one of the semesters,he sends half of his classes out for 10 minutes of recess prior to testing for the other half,he provides 10 minutes of free time after the test.Which of the following best represents the design of Hernandez's study?
A)Static-group comparison
B)Post-test only control group
C)Solomon four group
D)One-shot case study

Accepted Answer

Hernandez's study uses a static-group comparison design because it compares the performance of two groups (one that had recess before the test and one that did not) without using a pretest to measure their performance before the intervention.

Question 5

In experimental design,the variable that is manipulated is the:
A)dependent variable.
B)independent variable.
C)confounding variable.
D)constant.

Accepted Answer

The variable that is manipulated, or changed by the researcher, is the independent variable. The dependent variable is the variable that is measured or observed and is expected to be affected by the independent variable. Confounding variables are variables that can affect the dependent variable but are not controlled for in the experiment. Constants are variables that are kept the same throughout the experiment in order to ensure that any changes seen in the dependent variable are due to changes in the independent variable.

Question 6

Which of the following scenarios best exemplifies a multiple-baseline design?
A)Bryce is an occupational therapist working with Sandy,a brain-injured patient.Bryce has decided to test the effects of a graphing strategy with Sandy.He starts the graphing technique,while collecting data in the form of minutes of strength training per day.He discontinues the graphing technique still collecting minutes of strength training per day.Bryce then reintroduces the graphing technique.
B)Laura has developed a new treatment to increase spatial ability.She randomly assigns students to either her intervention or a control condition.In the treatment condition students engage in working puzzles for twenty minutes a day for 10 days.Unfortunately,students don't like her intervention and refuse to do puzzles for all of the days.
C)Mr.Matthews,the school psychologist,is called by the third-grade teacher because one of the students,Seamus,has been referred for a new behavioral intervention plan,in which the teacher uses nonverbal signals as a positive consequence when Seamus engages in appropriate behavior.Mr.Matthews observes Seamus's behavior in the regular classroom and in Art and Music class.He records off-task behavior,calling out,and touching others for eight days.
D)Ewa is an athletic trainer at the university.She conducts research on violence in sport.She has designed a study to examine the effects of a new sportsmanship class.She randomly assigns teams by sport to be in either her new class or not.That is,some teams are in the class and others are not.She then compares incidents of violence between groups.

Accepted Answer

The scenario in choice C involves a school psychologist observing a student's behavior in different settings, and changing the intervention (using nonverbal signals) at different times. This is a clear example of a multiple-baseline design, where observations are taken at different times with varying interventions. The other scenarios do not fit the definition of a multiple-baseline design.

Question 7

"There will be differences in degree of mood elevation seen in depressed clients after receiving either cognitive-behavioral or psychoanalytic therapy." In this hypothesis,mood elevation is the:
A)dependent variable.
B)independent variable.
C)confounding variable.
D)constant.

Accepted Answer

Mood elevation is the outcome or response we are measuring, thus it is the dependent variable. The independent variable would be the type of therapy (either cognitive-behavioral or psychoanalytic). Confounding variables would be any other factors that could potentially affect mood elevation, such as medication or the severity of depression, but are not explicitly manipulated in this study design. "Constant" is not applicable in this hypothesis.

Question 8

"There will be differences in degree of mood elevation seen in depressed clients after receiving either cognitive-behavioral or psychoanalytic therapy." During a test of this hypothesis,it was discovered that some of the participants lived with family members and others lived alone.This variable,living situation,is a/an _____.
A)independent variable.
B)dependent variable.
C)constant.
D)confounding variable.

Accepted Answer

The living situation is a confounding variable because it was not controlled for in the study and may affect the results by interacting with the type of therapy received. As a result, it is difficult to determine if any observed differences in mood elevation are due to the therapy or due to the living situation of the participants.

Question 9

Kathy trains nurses.She designed a new assertive communication unit to include in her training.She administers a pretest and then randomly assigns nurses to her treatment or a control condition.She tests their communication skills after the treatment.She sees significant differences at immediate testing but after eight weeks she retests the nurses and finds no differences between her treatment and control students.Which of the following best represents the design of Kathy's study?
A)Non-equivalent groups
B)Solomon four group
C)Pretest-posttest control group
D)Post-test only control group

Accepted Answer

Kathy used a pretest-posttest control group design, where the nurses were randomly assigned to either the treatment or control condition and were tested before and after the treatment. The lack of differences between the treatment and control groups at the eight-week follow-up indicates that any initial effects may have dissipated over time.

Question 10

Dr.Robbins wants to know if there are different opinions regarding the value of public school education between Native Americans who have at least one relative who attended Indian Boarding School and Native Americans who have no family experience with Indian Boarding School.Dr.Robbins contacts 35 Native American participants in each group.He wants each group to include younger as well as older adults,and a mix of male and female participants.He asks each person to complete a survey about their attitudes toward public education.The design of this study is:
A)pre-experimental
B)factorial
C)true experimental
D)ex post facto

Accepted Answer

The study is ex post facto because it examines the attitudes of participants based on an existing condition or characteristic (having a relative who attended Indian Boarding School vs. not having that family experience) that was not manipulated by the researcher.

Question 11

Millie is using a behavior checklist strategy as well as a prompted praise strategy when working with her second grade behavior disordered student,Kent.She uses both strategies within the same day going back and forth randomly between the two approaches,while recording his on-task behavior.Which of the following designs is Millie employing?
A)Multiple baseline
B)Alternating-treatments
C)Control group time series
D)Static group comparison

Accepted Answer

Millie is employing the alternating-treatments design, where she is alternating between the behavior checklist and prompted praise strategies to determine which one is most effective in increasing Kent's on-task behavior. This design allows for a direct comparison of the two interventions and the ability to determine which one is more effective. The other designs listed do not involve the use of alternating interventions.

Question 12

The primary difference between the Solomon four-group design and the two-factor experimental design is that ONLY the two-factor experimental design:
A)involves four groups of participants.
B)requires random assignment of participants to groups.
C)has a measurement before initial treatment.
D)includes two different treatments.

Accepted Answer

The Solomon four-group design involves four groups of participants and has a measurement before initial treatment, but it only tests the main effects of treatment and pretest sensitization. The two-factor experimental design includes two different treatments, requires random assignment of participants to groups, and allows for the testing of both main effects and interaction effects of the treatments.

Question 13

A meta-analysis is used when:
A)the researcher wishes to analyze the analyses of a number of existing studies.
B)there is little existing literature to use as a launching pad for a new study.
C)the researcher has no access to sophisticated statistical techniques.
D)several researchers jointly conduct a large-scale study.

Accepted Answer

A meta-analysis is used to analyze the analyses of a number of existing studies. This allows for the pooling of data from multiple studies to increase the sample size and potentially identify patterns or effects that are not visible in individual studies.

Question 14

A researcher is studying the effectiveness of two different resident adolescent drug treatment programs.Program A is used at Summerhill adolescent facility.Program B is used at Winterdale adolescent facility.Because random assignment to treatments is not possible in this situation,what can the researcher do to minimize possible effects of sample bias?

Accepted Answer

The answer of A researcher is studying the effectiveness of...

Question 15

PJ conducts an experimental study on the effects of soft music during high stakes science testing.He randomly assigns students at the school.In one condition he does not provide music for testing while in the other group he does provide the music.He administers a pretest at the beginning of the year and a posttest at the end of the year.PJ's design is best described as a:
A)Static group comparison
B)Pretest-posttest control group design
C)Control-group-time-series design
D)Nonrandomized control-group pretest-posttest design

Accepted Answer

This design involves two groups (one with music and one without) and both groups are measured at two different times (pretest and posttest). This is a pretest-posttest control group design.

Question 16

Dr.Dow Jones wants to know whether a problem-based approach to teaching economics will result in higher academic performance than his traditional method.Of the six sections of Economics 101 at his university,Dr.Jones randomly assigns three sections to the traditional method and three sections to the problem-based method.At the end of the semester,all students complete the same final exam.In this design,students studying under the traditional method constitute the:
A)placebo group.
B)treatment group.
C)sample.
D)control group.

Accepted Answer

The students studying under the traditional method are considered the control group because they are receiving the standard teaching method, which is being compared to the new, experimental (problem-based) approach.

Question 17

Russell's study compared GPA of those students who volunteered for academic study skills training and those who did not elect to take the training.He found that those who had the training also had higher GPA.With which validity threat should Russell be most concerned?
A)Maturation
B)Instrumentation
C)History
D)Selection

Accepted Answer

The study is comparing two groups, those who volunteered for academic study skills training and those who did not. This creates a selection threat, as the groups may not be equivalent and there may be other differences between the groups that could influence the results.

Question 18

"There will be gender differences in degree of mood elevation seen in depressed clients after receiving cognitive-behavioral therapy." In this hypothesis,gender is the:
A)dependent variable.
B)independent variable.
C)confounding variable.
D)constant.

Accepted Answer

In this hypothesis, the gender of the depressed clients is the independent variable, as it is being manipulated to see its effect on the degree of mood elevation after receiving cognitive-behavioral therapy. The dependent variable is the degree of mood elevation. A confounding variable would be something else that affects the degree of mood elevation, but is not being controlled for in the study. There is no constant in this hypothesis.

Question 19

In Katia's remedial mathematics study,she collected pretest data from a group of participants.She divided the participants into three groups.One group received no treatment,one group received instruction by a teacher-delivered intervention,one group received peer tutoring on the same problems.After the intervention she tested their math skills.With which validity threat should Katia be most concerned?
A)Maturation
B)Testing
C)Instrumentation
D)Attrition

Accepted Answer

Katia should be most concerned about the testing validity threat. This is because the participants were given a pretest before receiving the intervention, and then a post-test after the intervention. If the pretest had an effect on the participants' performance on the post-test, then the results may not accurately reflect the effectiveness of the intervention. This threat is known as the testing effect.

Question 20

Dr.Dow Jones wants to know whether a problem-based approach to teaching economics will result in higher academic performance than his traditional method.Of the six sections of Economics 101 at his university,Dr.Jones randomly assigns three sections to the traditional method and three sections to the problem-based method.At the end of semester all students complete the same final exam.In this design,students studying under the problem-based method constitute the:
A)placebo group.
B)treatment group.
C)sample.
D)control group.

Accepted Answer

The problem-based method is the treatment being tested in this experiment. Therefore, the sections of students studying under the problem-based method constitute the treatment group.

Quiz 7: Experimental, quasi-Experimental, and Ex Post Facto Designs

Factorial designs allow researchers to study the effects of more than one independent variable simultaneously.Why is this advantageous? What information can factorial designs yield that nonfactorial designs cannot?

In experimental design,the variable that is manipulated is the:

Which of the following scenarios best exemplifies a multiple-baseline design?

"There will be differences in degree of mood elevation seen in depressed clients after receiving either cognitive-behavioral or psychoanalytic therapy." In this hypothesis,mood elevation is the:

The primary difference between the Solomon four-group design and the two-factor experimental design is that ONLY the two-factor experimental design:

A meta-analysis is used when:

Russell's study compared GPA of those students who volunteered for academic study skills training and those who did not elect to take the training.He found that those who had the training also had higher GPA.With which validity threat should Russell be most concerned?

"There will be gender differences in degree of mood elevation seen in depressed clients after receiving cognitive-behavioral therapy." In this hypothesis,gender is the: