Question 1

Which type of variable is measured in both the experimental and control groups of an experiment?
A)the dependent variable
B)the independent variable
C)extraneous variables
D)the control variable

Accepted Answer

The dependent variable is what is being measured to compare the results between the experimental and control groups. Both groups are being tested on the same dependent variable, so it is measured in both groups. The independent variable is what is being manipulated in the experimental group to compare its effect on the dependent variable, and it may not be measured in both groups. Extraneous variables are variables that may affect the dependent variable but are not being intentionally manipulated or measured in the experiment. The control variable is a variable that is kept constant in both groups to ensure that any differences in the results are due to the independent variable, not outside factors.

Question 2

To equalize the intelligence of members of the experimental and control group in an experiment, you could use
A)extraneous control.
B)random assignment.
C)independent control.
D)subject replication.

Accepted Answer

Random assignment is the best choice to ensure equalization of intelligence between the experimental and control group. It involves randomly assigning participants to either group, which minimizes the chances of any pre-existing differences in intelligence between the two groups. Extraneous control refers to controlling for variables other than the independent variable, independent control is not a relevant term in this context, and subject replication refers to repeating the experiment with a different set of participants, which does not necessarily ensure equalization of intelligence between groups.

Question 3

A researcher wants to determine the effect of sleep loss on human problem-solving.Subjects in an appropriate control group for such an experiment would be described as having
A)much more sleep than normal.
B)much less sleep than normal.
C)a normal amount of sleep.
D)the same amount of sleep as the experimental group.

Accepted Answer

The control group for an experiment should receive a normal amount of sleep in order to provide a baseline for comparison to the experimental group, which will experience sleep loss. If the control group received either much less or much more sleep than usual, it would confound the results of the experiment, making it difficult to determine whether any observed effects are due to sleep loss or some other factor. The control group should always have similar characteristics to the experimental group, except for the variable being tested, which in this case is sleep loss. Therefore, option C is the best choice.

Question 4

In an experiment, control over extraneous variables, such as the time of day or the temperature of the room, can be obtained by
A)using a double-blind.
B)making all conditions except the independent variable exactly the same for all subjects.
C)using repeated measures.
D)observing and recording the impact of each variable on each subject in the experiment..

Accepted Answer

Making all conditions except the independent variable exactly the same for all subjects allows for control of extraneous variables. This helps to ensure that any observed effects can be attributed to the independent variable, rather than other factors that may differ between subjects or conditions. The other options (double-blind, repeated measures, observing and recording) may be useful in other contexts or for other purposes, but do not directly address the issue of controlling extraneous variables.

Question 5

One way to randomly assign students to experimental and control groups for a study of academic behaviors is to
A)flip a coin for each student to determine which group she or he will be assigned.
B)divide the group sitting in the front half of the room from the group sitting in the back.
C)ask volunteers for the experimental group to raise their hands.
D)do none of these.

Accepted Answer

Flipping a coin is a random and unbiased way to assign students to experimental and control groups. This eliminates any potential bias or manipulation from the researcher. The other options are not random and may lead to biased samples.

Question 6

In an experiment to study the effects of study skills training on academic achievement, the study skills training would be
A)the dependent variable.
B)an extraneous variable.
C)the control variable.
D)the independent variable.

Accepted Answer

The study skills training is being manipulated by the researchers and is expected to have an effect on the academic achievement, so it is the independent variable.

Question 7

A teacher wants to find out if a problem-based history program is superior to the regular history curriculum being used.The motivation and intelligence of the students participating in the new and the regular history programs would be considered the
A)independent variables.
B)dependent variables.
C)extraneous variables.
D)control variables.

Accepted Answer

Motivation and intelligence are extraneous variables because they are not the primary focus of the study but could influence the outcome, potentially affecting the results of the comparison between the two history programs.

Question 8

When subjects in an experiment are chosen so that each has an equal chance of being in either the experimental group or the control group, we say that the subjects have been assigned
A)alternately.
B)hypothetically.
C)randomly.
D)consecutively.

Accepted Answer

Random assignment ensures that there is no systematic bias in assigning subjects to either group, which is important for controlling for potential confounding variables and increasing the validity of the study's results.

Question 9

A researcher is testing the effectiveness of a new math program.The extraneous variables, such as temperature and lighting, will best be controlled by
A)randomly assigning students to rooms of varying temperature and light intensity.
B)randomly selecting the rooms in which the students will be taught.
C)making the temperature and the amount of light the same for all the rooms.
D)letting the students select the room temperature and lighting in which they are most comfortable.

Accepted Answer

To control extraneous variables such as temperature and lighting, it is best to keep them the same for all rooms. This way, any differences in the results can be attributed to the effectiveness of the math program and not to external factors. Option A would introduce variation and potentially confound the results, option B does not address the extraneous variables at all, and option D would introduce too much variation and make it difficult to draw meaningful conclusions.

Question 10

In an experiment to test whether teaching a new memory strategy will improve students' test scores, student characteristics, such as motivation, are controlled by
A)interviewing each student concerning their motivation in the class.
B)giving each student a personality test.
C)randomly assigning students to the two groups.
D)interviewing the teachers concerning each of the students.

Accepted Answer

Randomly assigning students to the two groups ensures that motivation levels are balanced between the two groups and any differences in test scores can be attributed to the new memory strategy taught rather than differences in motivation levels. The other options (interviewing each student about their motivation, giving personality tests, and interviewing teachers) may not accurately measure student motivation and do not provide a control for motivation levels between the two groups.

Question 11

The chief function of the control group in an experiment is that it
A)allows mathematical relationships to be established.
B)provides a point of reference against which the behavior of the experimental group can be compared.
C)balances the experiment to eliminate all extraneous variables.
D)it establishes causation.

Accepted Answer

The purpose of a control group is to serve as a standard of comparison for the experimental group, allowing researchers to determine if the changes observed in the experimental group are actually caused by the intervention being tested or by other factors. Without a control group, it would be difficult to distinguish the effects of the intervention from other unrelated factors that could be affecting the outcome of the study.

Question 12

Which of the following groups serves as a point of reference for a comparison of results in an experiment?
A)independent group
B)experimental group
C)control group
D)dependent group

Accepted Answer

The control group serves as a point of reference for comparison because it is not exposed to the independent variable and is used to establish a baseline for comparison with the experimental group. The experimental group is exposed to the independent variable, so it cannot be used as a reference point. The independent and dependent groups are not relevant terms in experimental design.

Question 13

A variable, such as the personality of a subject, that might affect the outcome of an experiment would be controlled by
A)random assignment of subjects.
B)assuming the effects of the variable are negligible.
C)manipulating the dependent variables simultaneously.
D)repeating the experiment several times until the results are consistent.

Accepted Answer

Random assignment of subjects allows for an equal distribution of potential confounding variables, such as personality traits, between experimental groups. This helps to control for the impact of these variables on the outcome of the experiment. Assuming the effects of the variable are negligible (B) is not a reliable method of control, as even small effects can impact the results. Manipulating the dependent variables simultaneously (C) is not relevant to controlling for potential confounding variables. Repeating the experiment several times until the results are consistent (D) can help to increase the reliability of the results, but does not necessarily control for potential confounding variables.

Question 14

A social psychologist measures aggressive responses made by people exposed to violent and nonviolent movies.All of the subjects are tested in rooms having identical room temperature.Thus, room temperature is a(n) _____ variable in the experiment.
A)correlated
B)independent
C)dependent
D)extraneous

Accepted Answer

Room temperature is not intentionally manipulated by the researcher and is not expected to have any effect on the aggressive responses of the participants. Therefore, it is an extraneous variable that should be controlled for but not treated as an independent or dependent variable. It is also not necessarily correlated with the other variables being studied.

Question 15

Random assignment of subjects to groups in an experiment is used to reduce the effects of
A)the independent variable.
B)the dependent variable.
C)experimenter bias.
D)extraneous variables.

Accepted Answer

Random assignment helps to reduce the effects of extraneous variables, which are variables that may influence the outcome of the study but are not the independent variable being studied. This helps to ensure that any differences observed between the groups are due to the independent variable and not other factors. Random assignment does not directly address issues of experimenter bias or the effects of the independent or dependent variables.

Question 16

Subjects are said to be assigned randomly when
A)they are selected to participate in an experiment from a sample which is representative of the larger population.
B)they each have an equal chance of being assigned to either the experimental or control group.
C)they are assigned to experimental and control groups so that the groups differ on some critical variable before the experiment begins.
D)neither the experimenter nor the subject knows whether the subject is in the experimental or control group.

Accepted Answer

Random assignment occurs when subjects have an equal chance of being assigned to either the experimental or control group. This is important in order to prevent selection bias and ensure that any differences between groups are due to the manipulation of the independent variable and not pre-existing differences between the groups themselves.

Question 17

We wish to test the hypothesis that music improves learning.Random assignment into two groups, one that listens to music and one that studies in silence, controls for
A)the students' inherent academic ability.
B)the students' use of different study strategies.
C)the amount of sleep students had prior to the experiment.
D)all of these.

Accepted Answer

Random assignment into two groups controls for all variables that could potentially affect the results, including the students' inherent academic ability, their use of different study strategies, and the amount of sleep they had prior to the experiment. This allows us to isolate the effect of the independent variable (music) on the dependent variable (learning).

Question 18

A researcher wants to find out if taking a new antidepressant drug will decrease the symptoms of subjects suffering from social anxiety.The number of symptoms exhibited by the subjects would be the
A)independent variable.
B)dependent variable.
C)extraneous variable.
D)control variable.

Accepted Answer

The number of symptoms exhibited by the subjects is what the researcher is interested in observing, and it will be measured after the subjects take the antidepressant drug. Therefore, it is the dependent variable. The independent variable is the drug being administered, the extraneous variables could be things like age, gender or disorders that might affect the results and the control variables could be things like dosage or frequency of administration that are kept constant to ensure they do not affect the results.

Question 19

Tina is assigned to a group where she receives the treatment.Nadine is in the group that does not receive the treatment.Identify the correct groups in which these two subjects have been placed.
A)Tina is in the independent group; Nadine is in the dependent group.
B)Tina is in the dependent group; Nadine is in the independent group.
C)Tina is in the control group; Nadine is in the experimental group.
D)Tina is in the experimental group; Nadine is in the control group.

Accepted Answer

Tina is receiving the treatment, which means she is in the experimental group. Nadine, who is not receiving the treatment, is in the control group. Therefore, choice D is the best answer.

Question 20

In a study of effects of alcohol on driving ability, the control group should be given
A)a high dosage of alcohol.
B)one-half the dosage given the experimental group.
C)a driving test before and after drinking alcohol.
D)no alcohol at all.

Accepted Answer

The control group should not be given any alcohol at all, in order to have a baseline for comparison with the experimental group who are given alcohol. This will allow researchers to isolate the effects of alcohol on driving ability.

Quiz 1: Extension B: Introduction to Psychology and Research Methods

Which type of variable is measured in both the experimental and control groups of an experiment?

To equalize the intelligence of members of the experimental and control group in an experiment, you could use

A researcher wants to determine the effect of sleep loss on human problem-solving.Subjects in an appropriate control group for such an experiment would be described as having

In an experiment, control over extraneous variables, such as the time of day or the temperature of the room, can be obtained by

One way to randomly assign students to experimental and control groups for a study of academic behaviors is to

In an experiment to study the effects of study skills training on academic achievement, the study skills training would be

A teacher wants to find out if a problem-based history program is superior to the regular history curriculum being used.The motivation and intelligence of the students participating in the new and the regular history programs would be considered the

When subjects in an experiment are chosen so that each has an equal chance of being in either the experimental group or the control group, we say that the subjects have been assigned

A researcher is testing the effectiveness of a new math program.The extraneous variables, such as temperature and lighting, will best be controlled by

In an experiment to test whether teaching a new memory strategy will improve students' test scores, student characteristics, such as motivation, are controlled by

The chief function of the control group in an experiment is that it

Which of the following groups serves as a point of reference for a comparison of results in an experiment?

A variable, such as the personality of a subject, that might affect the outcome of an experiment would be controlled by

A social psychologist measures aggressive responses made by people exposed to violent and nonviolent movies.All of the subjects are tested in rooms having identical room temperature.Thus, room temperature is a(n) _____ variable in the experiment.

Random assignment of subjects to groups in an experiment is used to reduce the effects of

Subjects are said to be assigned randomly when

We wish to test the hypothesis that music improves learning.Random assignment into two groups, one that listens to music and one that studies in silence, controls for

A researcher wants to find out if taking a new antidepressant drug will decrease the symptoms of subjects suffering from social anxiety.The number of symptoms exhibited by the subjects would be the

Tina is assigned to a group where she receives the treatment.Nadine is in the group that does not receive the treatment.Identify the correct groups in which these two subjects have been placed.

In a study of effects of alcohol on driving ability, the control group should be given