Research Methods
A researcher watches children interact on a playground without interfering with them. What research method is being used?
Naturalistic observation
A correlation describes what between two variables?
A relationship
What is the variable that a researcher intentionally manipulates?
Independent variable
What term describes whether a test measures what it is supposed to measure?
Validity
What field allows psychologists to analyze data collected from research?
Statistics
A researcher conducts an intensive investigation of one individual with an extremely rare psychological condition. What research method is this?
Case Study
If exercise increases while resting heart rate decreases, what type of correlation exists?
Negative correlation
What is the variable that a researcher measures to determine the effect of the independent variable?
Dependent variable
What term describes whether a test produces consistent results?
Reliability
Before participating in research, people must be given enough information to make an informed decision about participating. What ethical principle does this describe?
Informed consent
Researchers randomly select 300 high school students whose ages, sexes, and ethnic backgrounds closely reflect the entire school district. What type of sample are they trying to create?
Representative sample
Which represents the strongest correlation: +.20, −.81, +.56, or −.09?
−.81
Students are randomly assigned to study for 10, 30, or 60 minutes before taking the same test. What is the independent variable?
Amount of study time
Jamal takes the same personality test four times and receives nearly identical scores each time. What characteristic does this demonstrate?
Reliability
Participants report feeling better after receiving a pill containing no active medication because they believe they received the real treatment. What phenomenon occurred?
Placebo effect
A psychologist wants to learn how often teenagers check their phones during lunch. She sits in the cafeteria and secretly records how frequently students check their phones without interacting with them. Identify the research method.
Naturalistic observation
Researchers find that students who spend more time studying tend to earn higher test scores. Can researchers conclude that studying caused the higher scores?
No. Correlation does not prove causation.
A researcher studies whether caffeine affects reaction time. One group receives caffeine and another receives a caffeine-free drink. Neither the participants nor the researchers interacting with them know who received caffeine. What type of study is this?
Double-blind study
A teacher creates a test that consistently gives students almost identical scores each time they take it, but the questions do not actually measure the skill the teacher intended to assess. The test is ________ but not ________.
Reliable but not valid
What gives each participant an equal chance of being assigned to each condition and helps reduce systematic differences between groups.
random assignment
Researchers want to test whether exercise causes improved memory. They randomly assign participants to exercise for either 0, 20, or 40 minutes and then give everyone the same memory test. Identify the independent variable, dependent variable, and purpose of random assignment.
IV: Minutes of exercise
DV: Memory-test performance
Random assignment: Gives participants an equal chance of entering each condition and helps make the groups comparable.
A study finds r = −.76 between nightly sleep and daytime sleepiness. Explain both the strength and direction of the relationship.
It is a strong negative correlation; as sleep increases, daytime sleepiness tends to decrease.
A researcher examines whether music affects test performance. One group takes a test while listening to music and another takes it in silence. However, the music group takes the test in the morning while the silence group takes it in the afternoon. Identify the confounding variable.
Time of Day
A psychologist wants to determine whether sleep affects test performance. Students who choose to sleep 8 hours score higher than students who choose to sleep 4 hours. Why would this study have difficulty establishing cause and effect?
Students were not randomly assigned/manipulated, so other variables could explain the relationship.
A researcher tells participants they cannot leave the experiment once it begins, even if they become uncomfortable. What major ethical problem exists?
Participants have the right to withdraw from research.