Question 1

One reason a valid experiment may produce null results is:
A) the range of levels in the independent variable was insufficient to show an effect.
B) the dependent variable reflects a broad range of performance.
C) that the experiment is conducted in an environment that is too artificial.
D) that reactivity occurs in the participants (e.g.,they adopt the role of the "good subject").

Accepted Answer

A valid experiment may produce null results if the range of levels in the independent variable was insufficient to show an effect, meaning the variation in the independent variable might not have been enough to impact the dependent variable significantly.

Question 2

Dependent variables are:
A) manipulated by the researcher.
B) potential independent variables that are held constant.
C) measured by the researcher.
D) probable behavioral causes.

Accepted Answer

Dependent variables are the outcomes or effects that researchers measure in an experiment to see if changes occur due to the manipulation of independent variables.

Question 3

An experimental group or condition:
A) receives the level of interest of the independent variable.
B) receives the baseline level of the independent variable.
C) is often untreated.
D) is all that is required to conduct an experiment.

Accepted Answer

The experimental group or condition is the one that receives the level of interest of the independent variable, which is manipulated by the researcher to observe its effect on the dependent variable.

Question 4

The control group in an experiment:
A) fixes the level of a variable across all experimental conditions.
B) is often untreated.
C) receives the same levels of the independent variable as the experimental group.
D) refers to the manipulation of the independent variable.

Accepted Answer

The control group in an experiment is often untreated or receives a standard condition, serving as a baseline to compare with the experimental group, which receives the treatment or manipulation.

Question 5

A possible problem in generalizing from the decompression study on pregnant rats is that:
A) it is risky to generalize from ex post facto studies.
B) it is wrong to generalize from unethical research.
C) it is risky to generalize across species.
D) causality cannot be determined from observational research.

Accepted Answer

Generalizing findings from animal studies (such as those involving rats) to humans can be problematic due to significant biological, physiological, and psychological differences between species. This is why it's risky to generalize across species.

Question 6

When we do an experiment,we:
A) measure independent variables.
B) produce dependent variables.
C) produce control variables.
D) produce a comparison.
E) hold independent variables constant.

Accepted Answer

The answer of When we do an experiment,we:
A) measure independent...

Question 7

In experiments,the independent variable should be ____,the dependent variable should be ____ ,and the control variable should be ____.
A) controlled; constant; randomized
B) constant; an effect; causal
C) free; restricted; elevated
D) balanced; unconfounded; an effect
E) manipulated; measured; held constant

Accepted Answer

The independent variable is manipulated by the experimenter to observe its effect on the dependent variable, which is measured. Control variables are held constant to ensure that any observed effects can be attributed to the manipulation of the independent variable.

Question 8

Which of the following is not one of the ways that control is used in an experiment?
A) The control group is used as a basis of comparison.
B) The independent variable is under controlled manipulation.
C) The dependent variable is controlled by the researcher.
D) Extraneous variables are held constant.

Accepted Answer

The dependent variable is not controlled by the researcher; instead, it is observed to see how it changes in response to manipulations of the independent variable. Control in an experiment typically involves the control group, manipulation of the independent variable, and controlling extraneous variables, but not controlling the dependent variable.

Question 9

A variable that inadvertently causes an experimental result is:
A) confounded with the dependent variable.
B) confounded with the independent variable.
C) confounded with the control variables.
D) unlikely to be important in experiments.

Accepted Answer

A variable that inadvertently affects the experimental result is confounded with the independent variable, as it can influence the outcome and make it difficult to determine the true effect of the independent variable on the dependent variable.

Question 10

If you conducted a study on the effects of magnitude of food reward on maze learning in rats,you would probably make sure that your rats were food deprived several hours before each experimental session.You would do this:
A) to hold hunger,a dependent variable,constant.
B) to ensure a strong independent variable.
C) to ensure that the rats would not explore the maze.
D) to allow for generalization to "real" rat behavior.

Accepted Answer

Ensuring the rats are food deprived before each experimental session strengthens the motivation to seek food rewards, thus enhancing the influence of the food reward magnitude (the independent variable) on maze learning. This approach ensures that the rats are motivated by the food reward, making the independent variable (magnitude of food reward) more impactful on their learning behavior.

Question 11

In the research on decompression of pregnant rats,the independent variable was ____ ,a dependent variable was ____ ,and a control variable was ____.
A) reduced air pressure; behavioral tests; strain of rat
B) body weight; climbing ability; time of day
C) atmospheric pressure; age of rat; climbing ability
D) number of decompressions; body weight; home cage
E) experimental group; control group; test performance

Accepted Answer

In this research scenario, the independent variable is "reduced air pressure" because it is the condition being manipulated to observe its effect on the rats. A dependent variable is "behavioral tests" because it is what is being measured in response to changes in the independent variable. A control variable is "strain of rat" because it is kept constant to ensure that any observed effects on the dependent variable are due to changes in the independent variable, not differences in the genetic background of the rats.

Question 12

The "independence" of the independent variable means that it is free from:
A) experimental control.
B) influences from the participant.
C) manipulation.
D) restraints.

Accepted Answer

The independence of the independent variable means it is not influenced by the participant, ensuring that any changes in the dependent variable are due to the manipulation of the independent variable itself.

Question 13

According to Mill's joint method of agreement and difference:
A) when event A occurs,result X never happens.
B) X never happens in the absence of
C) X is caused by A if they occur together.
D) A and X vary inversely.

Accepted Answer

X never happens in the absence of A is the correct answer because according to Mill's joint method of agreement and difference, if an event (A) occurs and a result (X) never happens in the absence of A, then A is the cause of X.

Question 14

Control variables are:
A) potential independent variables that are held constant.
B) assigned to the control group.
C) measured by the experimenter.
D) potential dependent variables that are held constant.

Accepted Answer

Control variables are potential independent variables that researchers decide to keep constant to prevent them from influencing the outcome of an experiment, ensuring that any effects observed can be attributed to the independent variable being tested.

Question 15

Assume that your instructor wants to evaluate the effects of the intensity of surrounding light (in watts)on performance in a Nintendo game.Individuals who vary randomly in their initial skill level on the game are assigned to a room containing an overhead light at a selected intensity.Each participant plays the game in their assigned room at the same time of day,and their high score is measured.A control variable in this study is the ____.
A) level of light (in watts)
B) Nintendo game score
C) time of day
D) skill level

Accepted Answer

The time of day is a control variable in this study because it is kept constant for all participants to ensure that variations in performance are not due to differences in the time of day the game is played, which could affect factors like alertness and concentration.

Question 16

In the original Pepsi/Coke challenge,____.
A) preference was caused by the independent variable
B) labels and colas were confounded
C) people preferred Coke to Pepsi
D) preference and colas were confounded

Accepted Answer

In the original Pepsi/Coke challenge, the labels and colas were confounded, meaning that the participants' preferences could have been influenced by the brand labels rather than the actual taste of the colas.

Question 17

If a participant does too well on a task to observe meaningful differences in behavior,this would most accurately be referred to as:
A) a ceiling effect.
B) a floor effect.
C) luck.
D) a null result.

Accepted Answer

A ceiling effect occurs when the task is too easy, causing most participants to perform at or near the top, making it difficult to detect differences in performance.

Question 18

A floor effect occurs when:
A) the lowest possible score on the dependent variable is too high.
B) the highest possible score on the dependent variable is too high.
C) the lowest possible score on the dependent variable is too low.
D) the highest possible score on the dependent variable is too low.

Accepted Answer

A floor effect occurs when the lowest possible score on the dependent variable is too high, meaning that the measurement instrument cannot detect lower scores even if they exist. This can limit the range of observed outcomes and potentially bias the results of a study.

Question 19

In experiments,independent variables are:
A) the results of careful measurements of behavior.
B) extraneous to the experiment and held constant.
C) extraneous to the experiment and allowed to vary randomly.
D) independent of experimental control.
E) varied by the researcher.

Accepted Answer

Independent variables are those that are manipulated or varied by the researcher to observe their effect on dependent variables.

Question 20

Assume that your instructor wants to evaluate the potential effects of the amount of caffeine intake on performance in a motor coordination task (playing pinball).Following a specified dose of caffeine,individual scores on pinball are measured.Each participant plays pinball at the same time of day.Also,each participant has been matched for initial skill level at pinball.The independent variable in this study is ____.
A) dose level
B) pinball score
C) time of day
D) skill level

Accepted Answer

The independent variable is the variable that is manipulated by the researcher to observe its effect on another variable. In this study, the amount of caffeine intake (dose level) is manipulated to see its effect on performance in a motor coordination task (playing pinball), making it the independent variable.

Quiz 7: Basics of Experimentation

One reason a valid experiment may produce null results is:

Dependent variables are:

An experimental group or condition:

The control group in an experiment:

A possible problem in generalizing from the decompression study on pregnant rats is that:

When we do an experiment,we:

In experiments,the independent variable should be ,the dependent variable should be ,and the control variable should be .

Which of the following is not one of the ways that control is used in an experiment?

A variable that inadvertently causes an experimental result is:

If you conducted a study on the effects of magnitude of food reward on maze learning in rats,you would probably make sure that your rats were food deprived several hours before each experimental session.You would do this:

In the research on decompression of pregnant rats,the independent variable was ,a dependent variable was ,and a control variable was .

The "independence" of the independent variable means that it is free from:

According to Mill's joint method of agreement and difference:

Control variables are:

In the original Pepsi/Coke challenge,____.

If a participant does too well on a task to observe meaningful differences in behavior,this would most accurately be referred to as:

A floor effect occurs when:

In experiments,independent variables are: