Question 1

One of the authors of your textbook conducted a study on monitor size and reaction time.The research matrix is given below.
$$\begin{array} { | l | l | l | } 
\hline 17 \text { inch } & 19 \text { inch } & 21 \text { inch } \
\hline 25 \text { participants } & 25 \text { participants } & 25 \text { participants } \
\hline
\end{array}$$
If you wanted to give every participant in the study a piece of paper with the contact information of the researchers, how many pieces of paper will you need for this between subjects design?

Accepted Answer

Since this is a between subjects design, each participant will only receive one piece of paper. Therefore, the total number of pieces of paper needed is the sum of the number of participants in each group, which equals 25+25+25=75.

Question 2

In Chapter 8, we mentioned a study that examined the relationship between where one lives urban or rural) and when a specific form of cancer is diagnosed.For this example, the independent variable was where one lives.Which statement best explains why where one lives was a between subjects variable?

Accepted Answer

Where one lives (urban or rural) is a naturally occurring variable that cannot be manipulated by the researchers. Participants cannot live in both urban and rural settings at the same time, making it a between-subjects variable.

Question 3

In chapter 7, we used a between subjects design to see if caffeine influenced levels of alertness.We had three groups of participants: participants who received 8 ounces of a caffeinated beverage, participants who received 24 ounces of a caffeinated beverage, and participants who received no caffeine.If this was a between subjects design with 30 total participants, how many participants would be in each condition?

Accepted Answer

In a between subjects design, each participant is assigned to only one condition. With 30 total participants and 3 conditions, dividing equally means each condition has 10 participants.

Question 4

In the quasi-experimental birth weight study described in chapter 7, birth weight was the subject variable.Participants were born of either low birth weight or normal birth weight.For this study, birth weight __________.

Accepted Answer

Birth weight was the subject variable, meaning it was used to create two different groups of participants (low birth weight and normal birth weight). Therefore, it was a between subjects variable.

Question 5

Carefully review the research matrix presented below.If this is a between subjects design, how many total participants will be used in the experiment?
$$\begin{array} { | l | l | l | } 
\hline \text { No Caffeine } & 8 \text { Ounces } & 24 \text { Ounces } \
\hline 10 \text { participants } & 10 \text { participants } & 10 \text { participants } \
\hline
\end{array}$$

Accepted Answer

Each condition (no caffeine, 8 ounces, 24 ounces) has 10 participants, so the total number of participants in the experiment is 30.

Question 6

In Chapter 8, we mentioned a study that examined the relationship between where one lives urban or rural) and when a specific form of cancer is diagnosed.For this example, the independent variable was where one lives.How many levels did the IV have?

Accepted Answer

The independent variable in this study was where one lives, and it had two levels: urban and rural.

Question 7

Brigham and Women's Hospital conducted a study with two groups of participants.One group was allowed to experience deep sleep, while the other group was deprived of deep sleep.Next, participants in both groups completed a visual task.Results indicated that performance did improve on the visual task for participants in the group that experienced deep sleep.In this study, what type of research design was used?

Accepted Answer

A between-subjects design was used as there were two separate groups (one with deep sleep and one without) that were compared for their performance on the visual task.

Question 8

Farris et al.conducted a study to determine if men and women were equal in their ability to judge women's nonverbal cues.In this example, what was the DV?

Accepted Answer

The DV (dependent variable) is the variable being measured in the study, in this case, the researchers are measuring the ability to judge women's nonverbal cues. Therefore, C is the best choice.

Question 9

Darley and Batson conducted a study in which the independent variable was the degree to which the participants were instructed to hurry to the other building high-hurry, intermediate-hurry, low-hurry) and the dependent variable was the amount of help offered to a "victim" placed by the researchers between the two buildings.This was a between subjects design.Therefore, how many groups of participants were needed?

Accepted Answer

Since this was a between subjects design, each group had to be exposed to a different level of hurry manipulation. Therefore, three groups of participants were needed (high-hurry, intermediate-hurry, low-hurry).

Question 10

Brigham and Women's Hospital conducted a study with two groups of participants.One group was allowed to experience deep sleep, while the other group was deprived of deep sleep.Next, participants in both groups completed a visual task.Results indicated that performance did improve on the visual task for participants in the group that experienced deep sleep.In this study, what was the dependent variable?

Accepted Answer

The dependent variable in this study is the performance on the visual spatial task, as this is what was being measured and compared between the two groups. The independent variable is the condition of either experiencing deep sleep or being deprived of it. Options A and B are variations of the independent variable, while option D is not relevant as it was not being compared between the two groups in the study.

Question 11

You want to replicate Barlett et al.'s research on amount of blood in a video game and measures of aggression.Your independent variable has 4 levels: maximum blood, medium blood, low blood, and no blood.You want to conduct a between subjects design.How many total participants will you need if you want 10 participants in each level of the IV?

Accepted Answer

Since there are 4 levels of the independent variable and you want 10 participants for each level, you need a total of 4 * 10 = 40 participants.

Question 12

Which of the following statements regarding a between subjects design is correct?

Accepted Answer

In a between subjects design, each participant is randomly assigned to only one level of the independent variable, meaning they are exposed to only one level and not all levels.

Question 13

Farris et al.conducted a study to determine if men and women were equal in their ability to judge women's nonverbal cues.In this example, what was the IV?

Accepted Answer

The independent variable in this study is the sex of the participant, as the researchers are interested in comparing men and women's ability to judge women's nonverbal cues. The sex of the researcher and the ability to judge verbal cues are not relevant to the study's hypothesis.

Question 14

Brigham and Women's Hospital conducted a study with two groups of participants.One group was allowed to experience deep sleep, while the other group was deprived of deep sleep.Next, participants in both groups completed a visual task.Results indicated that performance did improve on the visual task for participants in the group that experienced deep sleep.In this study, what was one potential disadvantage?

Accepted Answer

Increased statistical variance could be a potential disadvantage in this study because the difference in sleep quality among participants could introduce more variability in the visual task performance outcomes, making it harder to detect the effect of deep sleep on performance.

Question 15

Sex of participant is always a __________.

Accepted Answer

Sex of participant is an example of a between subjects variable, as each participant can only be classified as male or female and cannot belong to both groups simultaneously.

Question 16

Brigham and Women's Hospital conducted a study with two groups of participants.One group was allowed to experience deep sleep, while the other group was deprived of deep sleep.Next, participants in both groups completed a visual task.Results indicated that performance did improve on the visual task for participants in the group that experienced deep sleep.In this study, what was the independent variable?

Accepted Answer

The independent variable in this study is the conditions of sleep, specifically whether or not participants experienced deep sleep.

Question 17

In a __________, participants will be exposed to only one level of the independent variable.

Accepted Answer

In a between subjects design, participants are randomly assigned to different groups, with each group being exposed to a different level of the independent variable. This allows for comparisons between groups and reduces the risk of order or practice effects that may occur in within subjects designs.

Question 18

Your friend Joe wants to know about the study on monitor size and reaction time described in question #10.Tell Joe how many groups it is possible that a particular participants would be exposed to given the nature of the design.

Accepted Answer

Given the nature of the design described, a participant would only be exposed to one of the three groups, indicating a between-subjects design where each participant is assigned to only one condition.

Question 19

You want to replicate Barlett et al.'s research on action figures and negative body image in young adult males.Your independent variable has three levels: no action figures, highly muscular figures, and moderately muscular figures.You want to conduct a between subjects design.How many total participants will you need if you want 10 participants in each level of the IV?

Accepted Answer

Since it is a between subjects design and there are three levels of the independent variable with 10 participants in each level, the total number of participants needed will be 30 (10 participants for each level).

Question 20

A research matrix is __________.

Accepted Answer

A research matrix is a visual representation of a research design. It typically involves organizing research questions, variables, and data collection methods into a grid format, allowing researchers to see the relationships between different aspects of their study. It is commonly used in psychology research and other social sciences.

Quiz 10: Between Subjects Designs