Deck 7: The Experimental Research Strategy

Question 1

Dr.Adams 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.Adams 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)100
B)50
C)2
D)1

Answer 1

C

Question 2

Dr.Jones 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.Jones 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.Jones 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

Answer 2

C

Question 3

If a researcher were doing an experiment to determine whether eating protein causes a sad mood,measurements of mood would be the ________ variable.

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

Answer 3

B

Question 4

The manipulated variable in an experiment is the

A)independent variable.
B)dependent variable.
C)extraneous variable.
D)confounding variable.

Question 5

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

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

Question 6

For an experiment comparing two treatments,the researcher selects participants so that each treatment condition has 20 males and 10 females.For this study,what method is being used to control participant gender?

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

Question 7

The goal of the experimental research strategy is to establish the existence of

A)a cause-and-effect relationship between two variables.
B)a relationship between two variables.
C)no relationship between two variables.
D)a bi-directional relationship between two variables.

Question 8

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)you cannot draw a conclusion about the causal relationship between the variables.

Question 9

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 10

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

A)extraneous variables.
B)confounding variables.
C)independent variables.
D)dependent variables.

Question 11

Manipulating an independent variable involves

A)exposing participants to at least one level of the independent variable.
B)exposing participants to at least two levels of the independent variable.
C)exposing participants to at least three levels of the independent variable.
D)measuring two or more behaviors and determining whether they are related.

Question 12

In an experiment,the score for each participant is obtained by measuring the __________ variable.

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

Question 13

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 14

Dr.Jones 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.Jones 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.Jones 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 15

A confounding variable is a variable that

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

Question 16

Dr.Jones 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.Jones 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.Jones measures the level of depression for the people living in the houses.In this study,the independent variable is

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

Question 17

Dr.Jones systematically varies the temperature in the laboratory (70,80,and 90 degrees)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)an unsystematic relationship between temperature and activity level.

Question 18

Dr.Jones 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.Jones 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.Jones measures the level of depression for the people living in the houses.In this example,how many dependent variables are there?

A)100
B)50
C)2
D)1

Question 19

The measured variable in an experiment is the

A)independent variable.
B)dependent variable.
C)extraneous variable.
D)confounding variable.

Question 20

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 21

What is the advantage of a laboratory study over a field study?

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

Question 22

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 23

What is the general purpose for using simulations and field studies?

A)to increase external validity
B)to increase internal validity
C)to verify that the manipulation of the independent variable was successful
D)to prevent extraneous variables from becoming confounding variables

Question 24

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.

Question 25

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

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

Question 26

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)a required component of all experiments.

Question 27

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)a field study.
C)a transported study.
D)a quasi-experimental study.

Question 28

A researcher systematically varies people's stress levels to examine the effects of stress on performance.The researcher includes a measure of stress as

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

Question 29

In an experiment,a researcher manipulates people's mood to determine what 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,the research should

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 30

Which of the following is the primary goal for randomizing an extraneous variable in an experiment?

A)increase the ability to generalize the results
B)avoid selection bias
C)ensure that the variable in the sample is representative of the variable in the population
D)minimize the likelihood that the variable is confounding

Question 31

What is the advantage of a field study over a laboratory study?

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

Question 32

An extraneous variable can be eliminated completely by

A)holding it constant.
B)using randomization.
C)manipulating the independent variable.
D)measuring the dependent variable.

Question 33

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 placebo effect?

A)placebo versus treatment
B)placebo versus no-treatment
C)treatment versus no-treatment
D)You only need to look at the scores in the placebo control condition.

Question 34

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

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

Question 35

Manipulation checks are particularly important when

A)there are small changes from one treatment condition to the other.
B)simulations are used.
C)a placebo is used.
D)the other three choices are all situations in which manipulation checks are important.

Question 36

A researcher has observed that people who suffer from an eating disorder tend to have lower self-esteem than people without a disorder.However,the researcher is not sure whether the lower self-esteem leads to an eating disorder or whether having an eating disorder leads to lower self-esteem.This is an example of

A)the directionality problem.
B)the third-variable problem.
C)the extraneous variable problem.
D)the confounding variable problem.

Question 37

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

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

Question 38

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,which of the following 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 39

A no-treatment control group is a condition in which participants

A)receive a zero-value of the independent variable.
B)receive the treatment.
C)receive a fake treatment.
D)receive a non-zero value of the independent variable.

Question 40

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 41

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 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

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

Question 44

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 45

An experiment must have at least two different levels for the independent variable.

Question 46

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

Question 47

An extraneous variable can be eliminated completely by holding it constant.

Question 48

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

Question 49

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

Question 50

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

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

Holding a specific variable constant guarantees that the variable cannot be a confounding variable.

Question 53

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

Question 54

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

Question 55

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 56

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 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

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 59

In an experiment examining how alcohol influences men's 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 60

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

Question 61

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

Question 62

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

Question 63

Explain how simulation and field studies increase external validity.

Question 64

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

Question 65

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

Question 66

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

Question 67

Describe and differentiate the three methods to control extraneous variables.