Deck 7: The Experimental Research Strategy.

Question 1

Why is a confounding variable unacceptable in a true experiment?

A)​It can distort the effect of the independent variable.
B)​It can disrupt the normal behavior of participants.
C)It threatens internal validity by providing an alternative explanation for the results.
D)​It creates a directionality problem that undermines a cause-and-effect conclusion.

Answer 1

C

Question 2

Dr.Fowler is interested in studying how indoor lighting can influence people's moods during the winter.A sample of 100 households is selected.Fifty of the homes are randomly assigned to the bright-light condition where Dr.Fowler replaces all the lights with 100-watt bulbs.In the other 50 houses,all the lights are changed to 60-watt bulbs.After two months,Dr.Fowler measures the level of depression for the people living in the houses.In this study,the independent variable is the ____.

A)​brightness of the lights
B)​level of depression
C)houses with 100-watt bulbs
D)​houses with 60-watt bulbs

Answer 2

A

Question 3

In an experiment,the purpose for manipulating the independent variable is to help ____.

A)​establish the direction of the relationship by showing that the dependent variable changes when you manipulate the independent variable
B)​eliminate the third variable problem because you decide when to manipulate rather than waiting for the variable to change
C)establish the direction of the relationship and help eliminate the third variable problem
D)​ensure that any effects of selection bias or other randomization failures are minimized

Answer 3

C

Question 4

A researcher is performing an experiment to determine whether eating protein causes a sad mood.Measurements of mood in this experiment would be the ____ variable.

A)​independent
B)​dependent
C)experimental
D)​controlled

Question 5

In an experiment,manipulation of the independent variable requires ____.

A)​creating one treatment condition defined by one level of the independent variable
B)​creating at least two treatment conditions defined by two different levels of the? independent variable
C)creating at least three treatment conditions defined by three different levels of the? independent variable
D)​measuring two separate variables to determine how they are related

Question 6

Dr.Nguyen is studying how the quality of breakfast influences academic performance for elementary school children.A sample of 100 children is selected.Fifty children are provided with a nutritious breakfast when they arrive at school each morning.The other 50 children are given a doughnut each morning.After three months,Dr.Nguyen records the academic achievement level for each child and compares the two groups of scores.In this example,how many levels are there for the independent variable?

A)​1
B)​2
C)50
D)​100

Question 7

If a study finds that there is a strong relationship between two variables,this means that ____.

A)​the first variable causes a change in the second variable
B)​the second variable causes a change in the first variable
C)you can draw the conclusion that each variable causes the other variable to change
D)​there is a relationship between the variables but causality has not been established

Question 8

The measured variable in an experiment is the ____ variable.

A)​independent
B)​dependent
C)extraneous
D)​confounding

Question 9

A researcher has observed that children who eat more sugar tend to show a higher level of activity than children who eat less sugar.However,the researcher suspects that the apparent relationship may be explained by the fact that some children have a higher rate of metabolism,which causes them to eat more and to be more active compared to children with a lower rate of metabolism who eat less and are less active.This is an example of the ____.

A)​directionality problem
B)​third-variable problem
C)extraneous variable problem
D)​manipulation check problem

Question 10

Dr.Ramos is interested in studying how indoor lighting can influence people's moods during the winter.A sample of 100 households is selected.Fifty of the homes are randomly assigned to the bright-light condition where Dr.Ramos replaces all the lights with 100-watt bulbs.In the other 50 houses,all the lights are changed to 60-watt bulbs.After two months,Dr.Ramos measures the level of depression for the people living in the houses.Assuming that the study uses people from different age groups,participant age would be a(n)____ variable in the experiment.

A)​dependent
B)​independent
C)extraneous
D)​confounding

Question 11

In an experiment,any variable that varies systematically with the treatment conditions and might influence the participants' scores is called a(n)____ variable.

A)matching
B)​dependent
C)extraneous
D)​confounding

Question 12

In order to establish an unambiguous relationship between two variables,it is necessary to eliminate the possible influence of ____ variables.

A)​extraneous
B)​confounding
C)independent
D)​dependent

Question 13

How do studies using the experimental research strategy differ from other types of research?

A)​Only experiments can demonstrate a cause-and-effect relationship between variables.
B)​Only experiments involve comparing two or more groups of scores.
C)Only experiments can describe the relationship between variables.
D)​Only experiments can demonstrate a bi-directional relationship between variables.

Question 14

The manipulated variable in an experiment is the ____ variable.

A)​independent
B)​dependent
C)extraneous
D)​confounding

Question 15

Research indicates the people who suffer from depression also tend to experience insomnia.However,it is unclear whether the depression causes insomnia or the lack of sleep causes depression.This is an example of the ____.

A)​directionality problem
B)​third-variable problem
C)extraneous variable problem
D)​manipulation check problem

Question 16

A confounding variable is a variable that influences the ____.

A)​dependent variable and varies systematically with the independent variable.
B)​independent variable and varies systematically with the dependent variable.
C)dependent variable and varies randomly with the independent variable.
D)​independent variable and varies randomly with the dependent variable.

Question 17

The specific treatment conditions that are used in an experiment are called the ____.

A)​levels of the independent variable
B)​levels of the dependent variable
C)control groups
D)​manipulation checks

Question 18

Dr.Hines is interested in studying how indoor lighting can influence people's moods during the winter.A sample of 100 households is selected.Fifty of the homes are randomly assigned to the bright-light condition where Dr.Hones replaces all the lights with 100-watt bulbs.In the other 50 houses,all the lights are changed to 60-watt bulbs.After two months,Dr.Hines measures the level of depression for the people living in the houses.In this example,the level of depression is the ____ variable.

A)​dependent
B)​extraneous
C)correlational
D)​independent

Question 19

In New York State,the winter months produce higher heating bills and higher levels of depression.Although the numbers show that higher heating bills are related to higher levels of depression,what is the most likely explanation for this relationship?

A)​cause and effect
B)​the directionality problem
C)the third-variable problem
D)​the extraneous variable problem

Question 20

Dr.Jones systematically varies the temperature in the laboratory (70,80,and 90 degrees Fahrenheit)while holding other variables constant,and observes that the participants' activity level decreases as the temperature increases.This illustrates ____.​

A)​a non-causal relationship between temperature and activity level
B)​a causal relationship between temperature and activity level
C)no relationship between temperature and activity level
D)​a nonsystematic relationship between temperature and activity level

Question 21

In an experiment,a researcher manipulates people's mood to determine whether changes in mood cause changes in memory performance.However,the researcher is not sure that the manipulation is really causing people's mood to change.In this case,what should the researcher do?

A)​Control mood by holding it constant.
B)​Control mood by matching it across treatment conditions.
C)Add a no-treatment control group in which mood is not manipulated.
D)​Add a manipulation check by measuring mood.

Question 22

A researcher moves an experiment out of the laboratory and into the real world.This type of research is called a ____.

A)​simulation study
B)​field study
C)transported study
D)​quasi-experimental study

Question 23

In an experiment comparing two treatments,the researcher assigns participants to treatment conditions so that each condition has 15 seven-year-old children and 10 eight-year-old children.For this study,what method is being used to control participant age?

A)​randomization
B)​matching
C)holding constant
D)​limiting the range

Question 24

A researcher moves the real world into the laboratory.This type of research is called a ____.

A)​simulation study
B)​field study
C)transported study
D)​quasi-experimental study

Question 25

What is the purpose for using a control group in an experiment?

A)​It provides a baseline to evaluate the size of the treatment effect.
B)​It minimizes the threat of a confounding variable.
C)It is necessary to ensure the internal validity of the study.
D)​It is necessary to ensure the external validity of the study.

Question 26

A researcher exposes people to a stressful situation (such as public speaking)to examine the effect of stress on depressed mood.The researcher includes a measure of stress as a ____.

A)​measure of the dependent variable
B)​measure of extraneous variables
C)control for confounding variables
D)​manipulation check

Question 27

A researcher designs a study to determine whether female preschoolers prefer sweetened or unsweetened cereal.The researcher uses a box of sweetened colorful cereal and a box of unsweetened tan colored cereal.The research finds that the group of preschoolers ate more of the sweetened colorful cereal and therefore prefers the sweetened cereal.Which two variables are confounded in this experiment?

A)​color of the cereal and children's gender
B)​color of the cereal and sweetness of the cereal
C)sweetness of the cereal and amount of eating
D)​children's gender and amount of eating

Question 28

Which technique provides useful information when there are small changes from one treatment condition to another,when simulations are used or when a placebo is used?

A)​random selection
B)​random assignment
C)no-treatment controls
D)​manipulation checks

Question 29

In an experiment,participants are usually assigned to treatments using random assignment.The reason for using random assignment is ____.

A)​to allow the experimenter to manipulate participant variables
B)​to allow the experimenter to manipulate environmental variables
C)to help control extraneous variables
D)​to increase the reliability of the outcome measures

Question 30

Dr.Kim varies the amount of caffeine given to three groups of participants (0,100,and 200 mg)and then observes the anxiety level for each group.The 0-mg condition represents the ____ group.

A)​experimental
B)​manipulation check
C)no-treatment control
D)​waiting-list control

Question 31

Researchers often use simulation experiments in an attempt to obtain the ____ of an experiment and still keep much of the ____ of research conducted in the real world.

A)​external validity; internal validity
B)​internal validity; external validity
C)experimental realism; mundane realism
D)​mundane realism; experimental realism

Question 32

Holding a variable constant is a technique for removing one threat to ____ but it can limit the ____ of an experiment.

A)​internal validity; external validity
B)​external validity; internal validity
C)internal validity; reliability
D)​external validity; reliability

Question 33

What is the primary goal for randomly assigning participants to treatment conditions in an experiment?

A)​Increase the ability to generalize the results.
B)​Avoid selection bias.
C)Ensure that the individuals in the sample are representative of the individuals in the population.
D)​Minimize the likelihood that a participant characteristic becomes a confounding variable.

Question 34

In an experiment,participants are randomly assigned to treatment conditions ____.

A)​to help protect the internal validity of the study
B)​to help protect the external validity of the study
C)to help protect both the internal and external validity
D)​as an alternative to manipulation of variables

Question 35

A researcher decides to use only male participants in an experiment comparing two treatment conditions.For this study,what method is being used to control participant gender?

A)​randomization
B)​matching
C)holding constant
D)​limiting the range

Question 36

In an experiment,a confounding variable is a(n)____.

A)​example of the third-variable problem
B)​example of the directionality problem
C)limitation on the ability to manipulate the independent variable
D)​threat to internal validity

Question 37

What is the advantage of a simulation compared to a traditional laboratory study?

A)​increased internal validity
B)​increased external validity
C)increased reliability
D)​elimination of history effects

Question 38

Although field studies tend to have higher external validity that traditional laboratory studies,they also tend to have ____.

A)​lower internal validity
B)​lower reliability
C)an increased risk of confounding from history effects.
D)​an increased risk of finding no effect of the manipulation

Question 39

Which characteristic is necessary for an extraneous variable to become a confounding variable?

A)​It must change systematically from one participant to the next.
B)​It must change systematically when the independent variable is changed.
C)It must have no systematic relationship with the dependent variable.
D)​It must have no systematic relationship to the independent or dependent variables.

Question 40

An experiment includes a treatment condition,a no-treatment control,and a placebo control.Which two conditions should be compared to determine the size of the effect that is actually caused by the treatment?

A)​placebo versus treatment
B)​placebo versus no-treatment
C)treatment versus no-treatment
D)​placebo control only

Question 41

Preventing an extraneous variable from becoming a confounding variable by holding it constant can result in a threat to external validity.

Question 42

A researcher intends to compare two different treatment conditions.Participants for the first treatment are selected and tested early in the school semester,and participants for the second treatment are selected and tested late in the semester.In this study,the time-of-testing represents a confounding variable.

Question 43

All experiments must have either a no-treatment control group or a placebo control group.

Question 44

The purpose of an experiment is to demonstrate that changes in one variable are responsible for causing changes in a second variable.

Question 45

A researcher reports that participants made fewer errors on a simulated air-traffic-control task when quiet background music was playing than when there was no music.For this study,the number of errors is the independent variable.

Question 46

Results from a research study indicate that athletes who were given an electrolyte drink had better endurance scores on a treadmill task than athletes who were given water.For this study,the independent variable is water versus electrolyte drink.

Question 47

In an experiment examining how alcohol influences male judgments of female attractiveness,one group of participants is given non-alcoholic beer before they make their judgments.This would be classified as a placebo control condition.

Question 48

An experiment comparing a treatment group with a no-treatment control group has no independent variable.

Question 49

Simulation and field studies are used to increase the external validity of experiments.

Question 50

In an experiment,the process of manipulation involves changing the value of the dependent variable from one treatment condition to another.

Question 51

Research results show that participants who shout their favorite curse words over and over can endure a painful stimulus longer than participants who shout a neutral word.For this study,the dependent variable is the amount of time that the pain is endured.

Question 52

In order to establish an unambiguous cause-and-effect relationship between two variables,it is necessary to eliminate the possible influence of extraneous variables.

Question 53

A recent study reports that the more sexual content that adolescents watch on TV,the more likely they were to engage in sexual behaviors.However,it is unclear whether the sexual content on TV leads to sexual behavior or whether sexual behavior leads to a preference for sexual content on TV.This is an example of the third-variable problem.

Question 54

If two variables are consistently related to one another,you can conclude that changes in one variable are causing changes to occur in the other.

Question 55

An experiment always involves comparing measurements obtained under one level of the independent variable with measurements obtained under another level of the independent variable.

Question 56

Manipulation checks are particularly important for simulations to ensure that the simulation is effective.

Question 57

To demonstrate a cause-and-effect relationship between two variables,a researcher must make one of the variables change rather than waiting for it to change naturally.

Question 58

The possibility that an extraneous variable can become a confounding variable is eliminated completely by holding it constant.

Question 59

Randomizing a variable such as participant gender guarantees that it will not become a confounding variable.

Question 60

Simulation involves bringing aspects of the real world into the laboratory.

Question 61

Describe the directionality problem and explain how researchers attempt to avoid this problem in an experiment.

Question 62

Explain how simulation and field studies increase external validity.

Question 63

Explain why control of extraneous variables is a necessary component of an experiment.

Question 64

Describe and differentiate the three methods to control extraneous variables.

Question 65

Describe one situation where a manipulation check might be appropriate and explain what the manipulation check is intended to accomplish.

Question 66

Explain the difference between a no-treatment control group and a placebo control group.

Question 67

Explain why manipulation of an independent variable is a necessary component of an experiment.