Question 1

Dr. Kiecolt-Glaser is a health psychologist studying whether stress impairs the body's ability to heal. In the highly stressfull week before final exams, dental students are given an oralpunch biopsy-a small sample of gum tissue is removed. The number of days for the oral wound to completely heal is recorded. The same dental students receive a second oral punchbiopsy during summer vacation. Once again, the number ofdays until the oral wound completely healed was recorded.What is the independent variable in this study?

Accepted Answer

The independent variable in this study is whether the oral wound was created during a high stress or low stress period, as this is the variable that is being manipulated by the researchers. The other answer choices are not related to the independent variable and are either dependent variables or extraneous variables.

Question 2

Your instructor notices that in many of his classes, the longer he lectures, the more student yawns he sees. This represents:

Accepted Answer

The answer of Your instructor notices that in many of...

Question 3

Professor Williams is investigating loneliness. Participants inthe study complete the UCLA Loneliness Scale to measure theirlevel of loneliness. They also answer questions on a surveyabout many aspects of their personal life. In analyzing the results of her study, Professor Williams finds that as the number of friends increases, the level of loneliness tends to decrease. This represents a _____ correlation.

Accepted Answer

A negative correlation occurs when one variable increases while the other decreases, as seen with the increase in the number of friends and the decrease in loneliness.

Question 4

Which of the following correlation coefficients represents thestrongest relationship between two factors?

Accepted Answer

The correlation coefficient of -.80 represents the strongest relationship between two factors because it is closest to -1 or 1, indicating a strong negative or positive correlation, respectively. A coefficient of +.38 suggests a moderate positive correlation, while coefficients of -.15 and +.03 suggest weak negative and positive correlations, respectively.

Question 5

After analyzing her data, Professor Nelson discovers that acorrelation coefficient of +.75 exists between the amount ofcoffee a person drinks and the degree of stress experienced.Professor Nelson can safely conclude that:

Accepted Answer

A correlation coefficient of +.75 indicates a strong positive relationship between coffee consumption and stress. This means that as coffee consumption increases, so does the degree of stress experienced. However, this does not necessarily suggest a causal relationship between the two variables. It is possible that individuals who experience more stress are more likely to consume more coffee, or that there is a third variable influencing both stress and coffee consumption.

Question 6

Which of the following is a definition of the experimental method?

Accepted Answer

The experimental method is a research method used to determine a cause-and-effect relationship between changes in one variable (the independent variable) and the effect that is produced on another variable (the dependent variable). The variables are carefully controlled or manipulated by the researcher, and participants are randomly assigned to different conditions to ensure that any observed effects can be attributed to the independent variable. This allows for precise conclusions about the relationship between variables to be made.

Question 7

Which of the following statements regarding correlational research is TRUE?

Accepted Answer

Correlational research only shows a relationship between two variables and cannot determine causality. Correlations do not show which variable is causing the other variable to change, they only show that there is a relationship between the two variables. Therefore, it is incorrect to use correlational research to draw conclusions about cause-and-effect relationships.

Question 8

Researchers at the Allied Mental Health Center are conducting a study to determine how quickly symptoms of depression arereduced by different forms of psychotherapy. What is the independent variable in this study?

Accepted Answer

The independent variable in this study is the form of psychotherapy used to treat depression. This is the variable that the researchers are manipulating and testing to see if it has an effect on the reduction of depression symptoms. The other options mentioned (change in symptoms of depression, method used to recruit participants, and cost of the study) are not independent variables in this study.

Question 9

Researchers at State University wanted to test the hypothesisthat distributed, or spaced, practice results in better retentionof material than massed practice or cramming. To find out ifthere is a cause-and-effect relationship, the researcher shoulduse:

Accepted Answer

The experimental method is the best choice to test the cause-and-effect relationship between distributed practice and retention of material. The researcher can manipulate the independent variable (practice method) and randomly assign participants to each condition to ensure that the results are not due to individual differences. The dependent variable (retention of material) can be measured and compared between the experimental and control groups. Correlational research methods, naturalistic observation, and survey/questionnaire research cannot establish causality.

Question 10

The factor or variable other than the ones being studied that, if not controlled, could affect the outcome of an experiment is the:

Accepted Answer

The extraneous variable is any factor other than the independent variable that could affect the outcome of an experiment. This variable needs to be controlled in order to ensure that any changes observed in the dependent variable are actually due to the independent variable being manipulated. A and C are incorrect because they refer to variables that are being studied or measured as part of the experiment. D is also incorrect as it refers to the end result or outcome of the study, rather than a specific variable that could affect the outcome.

Question 11

The research method that is used to demonstrate a cause-and-effect relationship between changes in one variable and the effects on another variable is called the:

Accepted Answer

The experimental method is the only research method that allows for the manipulation of one variable to observe the effect on another variable. It is used specifically to demonstrate a cause-and-effect relationship. The descriptive and correlational methods do not involve manipulation of variables, and the meta-analytic method involves statistical analysis of multiple studies rather than direct manipulation of variables.

Question 12

In an experiment, the dependent variable is:

Accepted Answer

The dependent variable is the factor that is measured for change and is influenced by the independent variable. It is not always equivalent to zero, measured only in the control group participants, or deliberately manipulated by the researcher.

Question 13

A perfect positive correlation:

Accepted Answer

A perfect positive correlation means that as one variable increases, the other variable also increases at the same rate. It does not necessarily mean a causal relationship between the two variables. Therefore, Option A and C are incorrect. Option D is also incorrect because it describes a perfect negative correlation, where the variables move in opposite directions.

Question 14

In an experiment, the independent variable is the variable thatis:

Accepted Answer

The independent variable is the variable that is deliberately manipulated by the researcher in order to observe the effect it has on the dependent variable. The other options do not accurately describe the independent variable.

Question 15

A study on parental use of corporal punishment found arelationship between parental socioeconomic status and use of corporal punishment. Put simply, as socioeconomic statusdeclines, rates of parents' use of corporal punishment rise. Thisfinding represents a:

Accepted Answer

The answer of A study on parental use of corporal...

Question 16

In an experiment, the factor that is observed and measured for change and is thought to be influenced by the independent variable is called the:

Accepted Answer

The dependent variable is the factor being observed and measured for change, and it is thought to be influenced by the independent variable. The extraneous variable is a variable that could influence the results but is not being intentionally manipulated, while the confounding variable is a variable that is unintentionally affecting the results. The treatment variable is the independent variable being intentionally manipulated. Therefore, the best choice for this question is C, the dependent variable.

Question 17

While conducting research on intelligence, the experimentes were very careful to control for unwanted variability in suchfactors as age, gender, ethnic background, socioeconomic status, and so on. They did this in order to avoid or minimizethe influence of:

Accepted Answer

Controlling for unwanted variability in factors such as age, gender, ethnic background, and socioeconomic status helps to avoid or minimize the influence of extraneous or confounding variables on the results of the research. Dependent or outcome variables are the variables being measured or tested in the study, demand characteristics refer to cues in the experiment that may influence the participants' behavior or responses, and practice effects refer to improvements in performance due to repeated exposure to the same task or stimuli.

Question 18

Positive correlation is to negative correlation as _____ is to_____.

Accepted Answer

The answer of Positive correlation is to negative correlation as...

Question 19

Several correlational studies all point to the conclusion that themore time students spend playing violent video games, thelower their grade point average tends to be. This means that:

Accepted Answer

Correlational studies only show a relationship between two variables, so it cannot be concluded that one variable causes the other. In this case, the negative correlation suggests that there is a relationship between playing violent video games and lower grades, but it is not clear which variable is causing the other. Therefore, option C is the correct answer.

Question 20

Researchers interested in how sleep deprivation affected performance randomly assigned participants to groups that had one, two, or three nights of sleep deprivation. Then they tested their reaction times on a standard motor reaction task.The dependent variable in this experiment was:

Accepted Answer

The dependent variable in this experiment is the performance on the standard motor reaction task, specifically the participants' reaction times. The amount of sleep deprivation and the amount of sleep needed following the experiment are independent variables. The frequency of participants falling asleep is not mentioned as a variable of interest in the experiment.

Quiz 1: Introductionand Research Methods