1. Chapter Two Research in Psychology

2. Question A researcher decides that he will measure
anxiety by the number of times that an
observed child bites his or her fingernails. This
researcher has identified nail-biting as his
_____________ of anxiety.
theory
hypothesis
data
operational definition

3. Answer Choice d is correct.
An operational definition describes the exact operations or methods that a researcher will use to measure a variable. (Chapter 2, Critical Thinking and Scientific Research section)

4. Question A measure that has good _________ will
yield consistent results.
operationality
validity
reliability
substantiation

5. Answer Choice c is correct.
The reliability of a measure refers to the degree to which results occur repeatedly. (Chapter 2, Critical Thinking and Scientific Research section)

6. Question
A scientist who employs naturalistic observation might be likely to study which of the following phenomena?
The thoughts of depressed individuals in social situations
The number of baths that teenagers take each week
The number of aggressive behaviors in a preschool classroom each morning
The motivation of a professional baseball player

7. Answer Choice c is correct.
Naturalistic observation involves watching and recording a phenomenon as it naturally occurs. (Chapter 2, Naturalistic Observation: Watching Behavior section)

8. Question
“An intensive examination of the behavior and mental processes associated with a specific person” is the definition of a(n) __________.
naturalistic observation
case study
survey
experiment

9. Answer Choice b is correct.
Case studies intensively examine some event or phenomenon in a particular individual, group, or situation. (Chapter 2, Case Studies: Taking a Closer Look section)

10. Question
In an experimental investigation of the effect of sleep on memory performance, the independent variable is __________.
the participants’ gender
the participants’ age
memory task score
amount of sleep

11. Answer Choice d is correct.
The independent variable is the variable manipulated by the experimenter. (Chapter 2, Experiments: Exploring Cause and Effect section)

12. Question
Which of the following typically makes the experimental group and the control group very similar before the independent variable is manipulated by the experimenter?
Random sampling
Random assignment
Counterbalancing
The double-blind design

13. Answer Choice b is correct.
Random assignment tends to spread the effects of uncontrolled variables randomly across the groups in an experiment. (Chapter 2, Experiments: Exploring Cause and Effect section)

14. Question
An experimenter in a clinical trial of a new antidepressant medication has made use of a double-blind design. This means that
she has given placebos to both the experimental group and the control group.
neither she nor the participants know who is receiving the placebo.
all participants are randomly assigned to be in either the experimental group or the control group.
participants are blindfolded twice each week.

15. Answer Choice b is correct.
A double-blind design is one in which neither the experimenter nor the participants know who is or is not receiving a placebo. (Chapter 2, Experiments: Exploring Cause and Effect section)

16. Question
__________ makes your sample representative of your population, whereas __________ makes your experimental group similar to your control group.
Truncation; objectivity
Random assignment; random sampling
Confounding; random sampling
Random sampling; random assignment

17. Answer Choice d is correct.
Random sampling helps ensure that the people in the sample are representative of the population from which they were chosen, whereas random assignment is used to create equivalence among various groups in the experiment. (Chapter 2, Selecting Human Participants for Research section)

18. Question
Which of the following is NOT one of the techniques used by behavioral genetics researchers to investigate the relative contributions of genes and environment to behavior?
Analogue studies
Twin studies
Family studies
Adoption studies

19. Answer Choice a is correct.
Twin studies, family studies, and adoption studies are all used by researchers in behavioral genetics to determine the relative contributions of genes and environment to behavior. (Chapter 2, Psychological Research Methods and Behavioral Genetics section)

20. Question
To eliminate the effects of extreme scores (outliers), which of the following might be the preferred measure of central tendency?
Mean
Median
Mode

21. Answer Choice b is correct.
The median is sometimes a better measure of central tendency than the mean because the median is less sensitive to extreme scores. (Chapter 2, Descriptive Statistics section)

22. Question
You would expect to find a __________ correlation between the number of siblings that you have and the amount of time that you get in the bathroom each morning.
negative
positive
zero

23. Answer Choice a is correct.
A negative correlation indicates that the variables are inversely related, thus you get less time in the bathroom as you have more and more siblings in your family. (Chapter 2, Correlation and Correlation Coefficients section)

24. Question
For which of the following relationships would you expect to find a negative correlation?
Amount of ice cream a person eats and that person’s weight
Number of hours a person studies each night and that person’s course grade
Number of absences a person has in a course and that person’s course grade
A person’s high school GPA and a person’s college GPA

25. Answer Choice c is correct.
A negative correlation indicates that the variables are inversely related; thus as a student is absent more and more in a course, he or she tends to get a lower grade in that course. (Chapter 2, Correlation and Correlation Coefficients section)

26. Question
Which of the following is the strongest correlation coefficient (r)?
+.81
+.76
-1.39
-.34

27. Answer Choice a is correct.
The strength of the correlation coefficient (r) is indicated by the size of the number, regardless of the positive or negative sign. Keep in mind that a correlation coefficient cannot have a value smaller than negative one or larger than positive one. (Chapter 2, Correlation and Correlation Coefficients section)