Chapter 8: Two-Group Design

Question 1

In an experimental design, you can identify a ________

Answer 1

cause-and-effect relationship

Question 2

What is the name when changes in 1 variable are associated with changes in another variable, and causality is determined?

Answer 2

covariation (tells us that 2 variables are related, but not the direction)

Question 3

What is a temporal precedence?

Answer 3

when changes in the suspected cause (treatment) occur before changes in the effect (outcome)

Question 4

What is the easiest way to establish temporal presedence?

Answer 4

in an experimental design

Question 5

What are extraneous variables?

Answer 5

factors separate from the intended treatment that might change the outcome

Question 6

To determine causality, we need to eliminate/control ____

Answer 6

extraneous variables

Question 7

How can we prevent extraneous variables?

Answer 7

random selection

Question 8

This type of validity looks at whether the IV is the only cause of change in behavior:

Answer 8

internal validity

Question 9

Looks at how closely the study mimics the real world and helps make the participant more involved:

Answer 9

mundane realism

Question 10

What is another method for getting participants to engage in the study and ensuring the reactions to the manipulation stay neutral?

Answer 10

experimental realism

Question 11

What type of experiment compares 2 groups or conditions, and is the most basic way to establish cause-and effect?

Answer 11

two-group experiment

Question 12

This group receives the key treatment in an experiment

Answer 12

experimental group

Question 13

This group serves as the comparison group and receives either NO treatment, or a different amount of the IV

Answer 13

control group

Question 14

What is experimental control?

Answer 14

the ability to keep everything between groups the same except for the one element we want to test in an experiment

Question 15

What is the “a-little-more-versus-a-little-less” approach?

Answer 15

The experimental group gets a little bit more of the treatment, while the control group gets a little less

Question 16

____ attention focuses on something important while screening out disctractions

Answer 16

selective

Question 17

What is “independence”?

Answer 17

the assumption that each participant represents a unique and individual data point

Question 18

T or F: in a random assignment, participants have an equal chance of being in any group

Answer 18

TRUE

Question 19

A _____ design matches 2 participants with similar scores and skills, and then randomly assigns them to different groups

Answer 19

matched-pair design

Question 20

A ______ helps determine whether changing or altering the independent variable was actually effective

Answer 20

manipulation check

Question 21

What does the effect size tell you?

Answer 21

how large the difference is between the means

Question 22

After running a t-test, when do we reject the null hypothesis?

Answer 22

when the p-level is LESS than .05

Question 23

An independent samples t-test is used when there is ___ IV with ___ levels/conditions, and is used to test if the 2 groups are different

Answer 23

1;2

Question 24

By first manipulating an independent variable and then measuring a dependent variable, experimental designs can establish the ____ that correlational designs often cannot

a) strength of covariation
b) pattern of covariation
c) temporal precedence
d) control of extraneous variables

Answer 24

c) temporal precedence
***the IV has to come before the effect (outcome)

Question 25

A student can actively listen to their professor and take detailed notes despite being in a noisy and distracting lecture hall. This requires: a) selective attention b) episodic memory c) memory transience d) a divided consciousness

Answer 25

a) selective attention

Question 26

Which is a problem associated with allowing participants to assign themselves to one of the two groups in an experiment? a) it becomes impossible to manipulate the IV b) the experiment will lack mundane realism c) scores will not be independent d) participants may more easily identify the purpose of the study

Answer 26

d) participants may more easily identify the purpose of the study

Question 27

In which case is there NOT convincing evidence to suggest that 2 groups are different? a) p = .001 b) p = .01 c) p = .03 d) p = .06

Answer 27

d) p = .06

Question 28

In a study examining whether restrictions on cell phone use result in differences in performance on a memory test, participants who couldn't check their phones scored approximately a latter grade lower than participants who could. The students who couldn't check resported being more distracted by their phones, consistent with the literature on: a) working memory b) thought suppression c) obedience d) conscientiousness

Answer 28

b) thought suppression

Question 29

In an experiment examining whether refraining from cell phone use one hour before bedtime leads to better sleep, degree of cell phone use would be considered the _____ variable, whereas sleep quality would be considered the _____ variable a) dependent; independent b) dependent; control c) independent; dependent d) control; independent

Answer 29

c) independent; dependent

Question 30

You conduct a simple experiment to determine if listening to music while taking a test improves students' test scores. You set the significance level at .05, and after running a t-test for independent means, you find that the p-value is p = .04. What does this p-value indicate about your research findings? a) students who do not listen to music while taking a test have a better chance of performing well on their test b) the research hypothesis must be incorrect because the significance level is so low c) the difference between the test scores of those students in the experimental group and those in the control group is statistically significant d) there is not enough evidence to suggest that there is a true difference between the two research groups

Answer 30

c) the difference between the test scores of those students in the experimental group and those in the control group is statistically significant

Question 31

Which of these requires examination using an experimental approach? a) the effect of practice on performance b) the relationship between height and weight c) the role of gender on athleticism d) the relationship between head circumference and intelligence

Answer 31

a) the effect of practice on performance

Question 32

A nonsystematic and nonbiased method of putting participants into groups that ensures that each participant has an equal chance of being in any group is called a) matched-pair design b) random assignment c) self-selection d) experimental control

Answer 32

b) random assignment

Question 33

If you are interested in determining whether fatigue causes a negative mood state you would need to conduct a(n) a) survey b) observational study c) experiment d) interview

Answer 33

c) experiment

Question 34

Dr. Akimoto conducts a correlational study that finds that the amount of sleep a person gets the night before a test is associated with their performance on that test. The results of Dr. Akimoto's study are able to demonstrate that there is _____ between the two variables of interest a) random assignment b) independence c) temporal precedence d) covariation

Answer 34

d) covariation

Question 35

Which of these BEST exemplifies a directional hypothesis in an experimental design? a) new drivers who take an enhanced driver's education course will have fewer accidents than those who take the traditional course b) as the age of drivers increases, the rate of accidents decreases c) there will be a difference in the number of accidents over the course of a year between new drivers and experienced drivers d) will younger drivers get into fewer accidents than older drivers?

Answer 35

a) new drivers who take an enhanced driver's education course will have fewer accidents than those who take the traditional course

Question 36

What is external validity?

Answer 36

The extent to which study findings can be generalized outside the data collection setting to other people at other times

Question 37

Sam hypothesizes that parents or caregivers assigned to play with their child for 30 minutes will have less distracted children when they are left with a stranger for 30 minutes. This is an example of what type of hypothesis? a) nondirectional hypothsis b) directional hypothesis c) null hypothesis d) casual hypothesis

Answer 37

b) directional hypothesis

Question 38

_________ _________ represents when participants become engrossed in the maniuplation of the study, to which they feel it influences them

Answer 38

experimental realism