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In order to be able to determine cause and effect, which of the following is most important for a researcher to incorporate into a planned study?

Possible Answers:

An independent variable directly manipulated by the researcher

A thorough consent form for subjects to sign prior to participation

A measurable dependent variable

Confidentiality measures that ensure subjects’ personal information is not distributed

Correct answer:

An independent variable directly manipulated by the researcher

Explanation:

While all of these are things that a good experiment should possess, the one that is most important for a study’s ability to generate conclusions about causal relationships is the presence of a true independent variable. The fact that the researcher manipulates this variable directly allows him or her to conclude that any changes in the dependent variable are related to the changes in the manipulated independent variable alone. Causal relationships could still be inferred from a study that does not have a consent form or proper confidentiality practices; however, this study would certainly be unethical. Even research studies that do not focus on causal relationships involve the measurement of dependent variables.

Which of the following terms is incorrectly matched with its definition?

Possible Answers:

Correlation: strength of a relationship between two variables

Control group: comparision group that receives no treatment or a placebo

Independent variable: factor manipulated by the researcher

Dependent variable: factor that is measured

Random assignment: each member of a group has an equal chance of being selected for a study

Correct answer:

Random assignment: each member of a group has an equal chance of being selected for a study

Explanation:

Random assignment is the only term that is incorrectly matched. Random assignment involves assignment to experimental and control groups. It ensures that each participant has an equal chance of being assigned to a group. On the other hand, random selection refers to each member of a group having an equal chance of being selected for the study. 

A(n) __________ research design involves studying a sample over a period of time. A(n) __________ research design involves studying a sample of people who differ on a characteristic at one point in time.

Possible Answers:

double-blind experiment. . . cross-sectional

longitudinal. . . cross-sectional

cross-sectional. . . longitudinal

experimental. . . meta-analysis

meta-analysis. . . experimental

Correct answer:

longitudinal. . . cross-sectional

Explanation:

Cross-sectional and longitudinal studies are both types of correlational studies that allow researchers to predict or draw conclusions from data. "Cross-sectional" studies allow researchers to examine how a sample differs on a specific characteristic at one point in time. "Longitudinal studies" involve following a sample over time. On the other hand, "experimental studies" include random selection, random assignment, and an independent variable that is manipulated. Causation can only be concluded from true experiments. In "double-blind experiments," both the researchers and participants are unaware of which groups are assigned as the experimental and control groups. Last, a "meta-analysis" allows researchers to look at several research studies and draw statistical conclusions. 

A researcher plans to divide a sample into two groups. One group will receive a new depression medication. The other group will receive a sugar pill. Both groups' depression scores will be measured using the Beck Depression Inventory. What is the dependent variable in this study?

Possible Answers:

Experimental group

Control group

Depression scores

Drug vs. sugar pill group

Random assignment 

Correct answer:

Depression scores

Explanation:

The independent variable is the specific group that participants are assigned to (i.e. drug vs. sugar pill group). The experimental group is the group that receives the intervention (i.e. new depression drug), while the control group is the group that receives no treatment or a placebo. The dependent variable in a study is what is being measured, which in the case of this study is depression scores. The term random assignment refers to each participant having an equal chance of being assigned to the experimental and control groups. 

Which of the follow is not true about projective and objective personality tests?

Possible Answers:

Projective tests involve interpreting responses to ambiguous stimuli

Objective tests are scored in a standardized, predetermined way

The Thematic Apperception Test is a projective test

The Rorschach Inkblot test is an objective test

Correct answer:

The Rorschach Inkblot test is an objective test

Explanation:

The key difference between projective and objective personality tests is the way they are scored. Objective tests, which often involve self-report methods and “true/false” or multiple choice questions, are scored in a standardized, predetermined way. For example, if Joe and Anne both bubble in the exact same set of answers for a certain personality test, their score reports will show the exact same results. Contrastingly, projective tests generally don’t use a hard-coded method of scoring participant responses. Instead, the psychologist interprets a freeform response to an ambiguous stimulus and attempts to infer meaning from it, sometimes using guides created for this task as a reference. Both the Thematic Apperception Test (TAT) and the Rorschach Inkblot Test are projective tests. The TAT uses ambiguous, uncaptioned scenes as the ambiguous stimuli, while the Rorschach uses monotone, symmetrical inkblot splatters as the ambiguous stimuli.

Which of the following is the best example of naturalistic observation?

Possible Answers:

Giving one group of subjects a piece of chocolate and one group a sour candy and seeing who performs better on cognitive tasks

Asking a participant to give a short speech about a dream job, recording it, and later noting how many seconds she paused while speaking

Counting the number of trials it takes an infant child to successfully grip a ball and put it in a basket (from behind a two-way mirror)

Sitting on a park bench and tallying the number of times a parent tells their child to be careful versus to have fun

Correct answer:

Sitting on a park bench and tallying the number of times a parent tells their child to be careful versus to have fun

Explanation:

Naturalistic observation refers to watching individuals in their “natural habitat” when laboratory observation would be cost-prohibitive, impossible, or otherwise unrealistic. The defining feature of naturalistic observation is watching individuals and recording data about their behaviors in the normal, unaltered environment. This can be useful when the individuals might change their behavior when they are aware they’re being watched (i.e. a phenomenon sometimes called the Hawthorne effect). The example involving sitting at a park is naturalistic observation, because the researcher is observing the behavior of parents of children at play in their natural environment, as opposed to bringing the parent-children pairs into a lab and then observing the parents’ behavior. The other examples all involve bringing human subjects into a lab setting, which by definition is not naturalistic observation.

Which of the following processes is known as the brain imaging technique that involves amplifying electrical impulses recorded from electrodes on the scalp?

Possible Answers:

Electrocardiography (ECG)

Electroencephalography (EEG)

Positron emission tomography (PET)

Functional magnetic resonance imaging (fMRI)

Correct answer:

Electroencephalography (EEG)

Explanation:

The correct answer is "electroencephalography (EEG)." In EEG, the researcher applies electrodes to the participant’s (or patient’s) scalp and records the electrical signals emitted by the brain. Recall that neurons communicate with one another using electrical impulses. The electrodes are placed in specific places that allow the researcher to measure activity in different areas of the brain. This technique is often used in sleep research.

Which of the following is NOT true about double blind studies?

Possible Answers:

Participants are unaware which group they have been assigned to

Researchers gather correlational data to draw conclusions

There is a control group and at least one experimental group

Researchers are unaware which group the participants have been assigned to

The control group participants often receive a placebo treatment

Correct answer:

Researchers gather correlational data to draw conclusions

Explanation:

Double blind studies collect experimental data to draw conclusions, not correlational data! In other words, researchers are able to examine cause and effect relationships due to the random assignment of participants to a control group or an experimental group.

What kind of statistical test would be used to determine if there is a linear relationship between two variables?

Possible Answers:

Chi-square

Average

Pearson correlation

T-test

ANOVA

Correct answer:

Pearson correlation

Explanation:

A Pearson correlation between two variables indicates that as one variable increases, another variable either increases or decreases by some amount in a linear manner.

A study finds a strong negative correlation between the amount of chocolate a child consumes and the number of absences the child has from school. Which of the following values could express that correlation?

Correct answer:

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