Question 1

What is a "placebo" in experimental research?
A)When an experimenter deceives subjects about the experiment's true nature,then later tells them what it is really about
B)When subjects in a control group are treated the same as the subjects receiving the treatment
C)When subjects in the control group receive a false or empty treatment so they do not adjust their behaviour to confirm the experimenter's hypothesis
D)When neither the subjects nor an assistant helping the experimenter know specifics about the treatment or how hypothesis is being tested
E)When an event outside the experiment's control occurs during the experiment and affects the dependent variable

Accepted Answer

A placebo in experimental research is a treatment that has no therapeutic effect but is given to participants in a control group to mimic the experience of receiving an active treatment. This is done to ensure that any changes in the dependent variable observed in the treatment group are actually due to the treatment and not just a result of participants' expectations or other non-specific factors. Placebos are often used in drug trials, where participants may receive a sugar pill or injection of saline solution instead of the actual drug being tested. Option A describes deception in research, which is unethical. Option B describes a control group but not a placebo. Option D describes a double-blind study, which is different from a placebo. Option E describes an extraneous variable that might affect the dependent variable, but it is not a placebo.

Question 2

What term best describes the following experimental design notation? 0 0 0 0 0 0 0 0 0 0 X 0 0 0 0 0 0 0 0
A)Classical experiment
B)Solomon four-group
C)Interrupted time series
D)Equivalent time series
E)Two-group post-test only

Accepted Answer

This is the notation for an interrupted time series design, where measurements are taken at regular intervals before and after an intervention (represented by the "X" in the middle). This design is used to assess the effect of the intervention on the outcome of interest over time.

Question 3

While studying rates of language acquisition for new Canadians from different countries,Curtis Cunning's research assistants informed him that 7 of the 65 subjects had quit and walked out before the study was completed.What type of threat to internal validity does Curtis' experiment have?
A)Selection bias
B)History effect
C)Experimental mortality
D)Maturation
E)Testing effect

Accepted Answer

Experimental mortality refers to when participants drop out or withdraw from a study, which can create bias and affect the validity of the results. In this case, the 7 participants who quit could have had different language acquisition rates than those who completed the study, which could affect the overall results and conclusions drawn from the study.

Question 4

A local mayoral candidate hired Xavier Xed to test whether the method of distributing campaign literature resulted in more people voting for a candidate.He distributed campaign literature about the mayoral candidate to the Stevenson neighbourhood in a bright blue envelope that a volunteer placed at each person's front door.He distributed the same campaign literature about the candidate to residents of the Fairwinds neighbourhood by mailing it in a plain white envelope.He later learned that Stevenson was a low-income area of the city that was almost entirely Filipino,foreign-born,and 95 percent Catholic.Fairwinds was an upper-income area in the city and its residents were 100 percent white,Canadian-born Protestants.What problem with internal validity might threaten the results of his experiment?
A)Selection bias
B)History effect
C)Experimental mortality
D)Maturation
E)Testing effect

Accepted Answer

The problem with internal validity that might threaten the results of the experiment is selection bias. This is because the two neighborhoods that were chosen for the experiment have significant differences in demographics and socioeconomic status which could affect the way they respond to the campaign literature. The different responses could then skew the results of the experiment.

Question 5

Professor Ronald Ronaldson conducted an experiment to test changes in sex roles.The experimental group read 15 articles about the achievements of great and wonderful women.The control group read 15 articles about cooking,automobiles,astronomy,and accounting.During the lunch break,subjects from the experimental and control groups met and talked about what they were reading.What internal validity problem may occur?
A)Testing
B)Maturation
C)Diffusion of treatment
D)Experimental mortality
E)Hawthorne effect

Accepted Answer

The internal validity problem that may occur is diffusion of treatment, where the experimental group participants may share information about the articles they read with the control group participants. This can lead to contamination of the control group, making it more difficult to determine if any differences between the groups are due to the treatment (reading about great women) or due to the diffusion of treatment.

Question 6

Several people criticized Professor Peggy Pandemonium's experiment on "the effects of density of living conditions on aggression" for its external validity problems.This means her study had problems with
A)randomization to the experimental or control group.
B)generalizability.
C)ethics.
D)post-test effects.
E)selection of subjects into experimental and control groups.

Accepted Answer

External validity refers to the extent to which the findings of a study can be generalized to other populations or settings. Criticism of the experiment's external validity suggests that the study's findings may not be applicable to real-world situations beyond the specific conditions of the experiment.

Question 7

The __________ receives the treatment; the __________ does not receive the treatment.
A)Treatment; placebo
B)Experimental; quasi-experimental
C)Quasi-experimental; experimental
D)Control; experimental
E)Experimental; control

Accepted Answer

The experimental group would receive the treatment and the control group would not receive the treatment. This is the most common design in experimental research.

Question 8

Doris Denning wanted to study the relationship between high school students' grades and assessments of their teachers.After teaching her research assistants proper interviewing techniques,Doris provided them with fake transcripts and disciplinary histories,which depicted some students as exceptional and others as trouble-makers.In reality,the 'exceptional' students and 'trouble-makers' were labelled as such randomly.Once the assistants' interviews concluded,the data indicated 'exceptional' students held their teachers in much higher esteem than the 'trouble-makers.' What threat to internal validity does Doris' study most likely have?
A)Testing effect
B)Selection bias
C)Diffusion of treatment
D)Experimenter expectancy
E)Hawthorne effect

Accepted Answer

The answer of Doris Denning wanted to study the relationship...

Question 9

The Ontario provincial government banned smoking in public places and workplaces in 2004.Dr.Sandy Smokesless used public records to compare the incidence rates of lung cancers before and after 2004 to determine whether the smoking ban helped address the threat smoking poses to the health of Ontarians.What sort of experimental research is this?
A)Factorial design
B)Natural experiment
C)Latin square design
D)Interrupted time series design
E)Field research

Accepted Answer

The answer of The Ontario provincial government banned smoking in...

Question 10

Researcher Zoe Zednick wanted to test the effectiveness of a new anger management treatment session at the Prairie County social work agency.She assembled 24 clients who had been referred for anger management and divided them randomly into two groups of 12.One group was assigned to the new anger management session while the other group went to a traditional anger management session.Each group was given an intake assessment that measured anger management skills.After clients finished the sessions,Zednick measured the level of anger management skills for all subjects in both groups.What experimental design did she use?
A)Classical experiment
B)One-shot case study
C)Time series
D)Static group comparison
E)One-group pretest-post-test

Accepted Answer

The answer of Researcher Zoe Zednick wanted to test the...

Question 11

The Solomon four-group design combines which two other designs?
A)Case study and two-group post-test only
B)Classical experimental and equivalent time series
C)One-group pretest-post-test and static group comparison
D)Classical experimental and two-group post-test only
E)Classical experimental design and static group comparison

Accepted Answer

The Solomon four-group design combines both classical experimental design and two-group post-test only design. The two-group post-test only design is used as a control group to compare against the experimental group, while the classical experimental design involves pre-testing, treatment, and post-testing of both groups. The Solomon four-group design takes it a step further by also including two additional groups that are not pre-tested, allowing for a comparison of the effect of pre-testing on the experimental group.

Question 12

Field experiments,compared to laboratory experiments,generally have
A)lower external validity and higher internal validity.
B)higher external validity and lower internal validity.
C)lower external validity and lower internal validity.
D)higher external validity and higher internal validity.
E)equal external and internal validity.

Accepted Answer

Field experiments take place in a natural setting, which means the results can be generalized to a larger population. This increases the external validity but may decrease the internal validity as there are more factors that cannot be controlled. In laboratory experiments, the environment is controlled, giving a high internal validity but may limit generalizability to real-world settings.

Question 13

If the time between the pretest and the post-test is very short,then
A)the history effect is more likely to occur.
B)the statistical regression effect is less likely to occur.
C)the testing effect is more likely to occur.
D)the maturation effect is less likely to occur.
E)the statistical regression effect is more likely to occur.

Accepted Answer

The answer of If the time between the pretest and...

Question 14

An advertising firm hired by Multinational Motors wants to demonstrate that its advertising campaigns improve Canadian public perceptions of Multinational Motors' vehicles.The advertising firm surveys Canadians every year over the course of its 10-year contract with Multinational Motors.Each year,Canadian public perceptions of Multinational Motors increased with the exception of 2009.Just prior to conducting the 2009 survey,Multinational Motors was forced to recall an entire line of vehicles with defective brake systems,which resulted in several,highly-publicized deaths.What threat to internal validity might the results of the 2009 survey reflect?
A)Testing effect
B)Mortality
C)Maturation
D)History effect
E)Instrumentation

Accepted Answer

The results of the 2009 survey could reflect a history effect, as the highly-publicized deaths resulting from the defective brake systems may have influenced the public's perception of Multinational Motors' vehicles.

Question 15

An experimenter uses a "2 x 3" design.To what exactly do the numbers refer?
A)A factorial design with two independent variables and three dependent variables
B)A time series design with two dependent variables and three observations
C)A Latin square design with three groups
D)A factorial design with two categories in one treatment and three in the other
E)A static group comparison design with six dependent variables

Accepted Answer

The answer of An experimenter uses a "2 x 3"...

Question 16

Which of the following is NOT one of the pragmatic,common sense ideas that accounts for the difference between the successful research projects of an experienced researcher and the difficulties a novice researcher faces?
A)Post-experiment interviews
B)Planning
C)Pre-experiment interviews
D)Pilot tests

Accepted Answer

The other options (post-experiment interviews, planning, pilot tests) are all pragmatic, common sense ideas that experienced researchers use to make their projects successful. However, pre-experiment interviews are not typically considered as a key difference between experienced and novice researchers.

Question 17

What does the Hawthorne effect refer to?
A)Research that takes place in a natural setting
B)Research that takes place in an artificial setting
C)A treatment that has no effect in an experiment.
D)The effect that occurs when a researcher measures the dependent variable measure such that all the subjects get a perfect,or near perfect score.It means that by random chance alone the scores are likely to be lower the next time the same subjects are measured.
E)A situation in which subjects react to the fact that they are in an experiment more than they react to the treatment

Accepted Answer

The Hawthorne effect refers to a situation in which subjects in an experiment react to the fact that they are in an experiment more than they react to the treatment. This can lead to artificially inflated results and can be problematic for the validity of the study.

Question 18

Graduate student Fanny Feisty designed and produced a 30-second radio commercial for Reliable Randy's Used Cars.Next,she had the three most widely listened to local radio stations air the commercial 15 times a day for two weeks.She waited until the end of the two-week period and then called Randy to check on his recent sales.What experimental design did she use?
A)Classical experiment
B)One-shot case study
C)Time series
D)Static group comparison
E)One-group pretest-post-test

Accepted Answer

The answer of Graduate student Fanny Feisty designed and produced...

Question 19

Interaction effects occur when
A)there is an imbalance in the experimental and control group at the beginning of an experiment during the pretest.
B)there is experimenter expectancy and there is a diffusion of the treatment at the same time.
C)external validity and reactivity cannot be controlled by a double-blind experimental design.
D)in a factorial design,the impact of two variables operating in combination is greater than each of them added together.
E)instrumental effects cause history effects to get larger and ruin the post-test.

Accepted Answer

Interaction effects occur in a factorial design when the impact of two variables operating in combination is greater than each of them added together.

Question 20

Which of the following is least suited to providing clear evidence about a causal relationship between two variables?
A)Classical experimental design
B)Solomon four-group design
C)Post-test only control group design
D)One-shot case study
E)All of the above are equally effective.

Accepted Answer

The one-shot case study design is the least suited for providing clear evidence about a causal relationship between two variables. This design involves a single group receiving an intervention, and then observing the outcome; there is no comparison group or control condition. Therefore, it is difficult to establish causality or rule out alternative explanations for the outcome. The other designs listed (classical experimental, Solomon four-group, and post-test only control group) are better suited for providing clear evidence of a causal relationship between variables.

Quiz 9: Experimental Research

What is a "placebo" in experimental research?

What term best describes the following experimental design notation? 0 0 0 0 0 0 0 0 0 0 X 0 0 0 0 0 0 0 0

While studying rates of language acquisition for new Canadians from different countries,Curtis Cunning's research assistants informed him that 7 of the 65 subjects had quit and walked out before the study was completed.What type of threat to internal validity does Curtis' experiment have?

Several people criticized Professor Peggy Pandemonium's experiment on "the effects of density of living conditions on aggression" for its external validity problems.This means her study had problems with

The receives the treatment; the does not receive the treatment.

The Solomon four-group design combines which two other designs?

Field experiments,compared to laboratory experiments,generally have

If the time between the pretest and the post-test is very short,then

An experimenter uses a "2 x 3" design.To what exactly do the numbers refer?

Which of the following is NOT one of the pragmatic,common sense ideas that accounts for the difference between the successful research projects of an experienced researcher and the difficulties a novice researcher faces?

What does the Hawthorne effect refer to?

Interaction effects occur when

Which of the following is least suited to providing clear evidence about a causal relationship between two variables?