AP Psychology Module 1 Vocabulary

Critical Thinking

The ability to analyze information carefully, question assumptions, and evaluate evidence before forming conclusions.

Hindsight Bias

The tendency to believe, after learning an outcome, that you would have predicted it ("I knew it all along").

Confirmation Bias

The tendency to search for or interpret information in ways that confirm existing beliefs.

Overconfidence

Being more confident in your judgments or answers than is justified by actual accuracy.

Theory

An explanation that organizes observations and predicts outcomes.

Hypothesis

A testable prediction derived from a theory.

Falsifiable

Able to be tested and potentially proven wrong.

Operational Definition

A precise description of how variables are measured or manipulated in a study.

Replication

Repeating a study to see if the same results occur again.

Peer Reviewers

Experts who evaluate research before it is published.

Non-Experimental Methodology

Research methods that observe behavior without manipulating variables.

Case Study

An in-depth examination of one individual or small group.

Naturalistic Observation

Observing behavior in a natural environment without interference.

Meta-Analysis

A statistical technique that combines results from many studies to find overall trends.

Survey

A method of collecting data by asking people questions.

Social Desirability Bias

Participants respond in ways they think are socially acceptable.

Self-Report Bias

Inaccurate responses due to poor memory or dishonesty.

Experimenter Bias

Researcher expectations influence results.

Population

The entire group that is being studied.

Sample

A subset of the population.

Random Sample

Every member of the population has an equal chance of being selected.

Convenience Sampling

Selecting participants who are easily accessible.

Representative Sample

A sample that accurately reflects the population.

Sampling Bias

When a sample does not represent the population well.

Correlation

A relationship between two variables.

Correlation Coefficient (r)

A number between -1 and +1 indicating strength and direction of a relationship.

Variable

Any factor that can change and be measured.

Illusory Correlation

Perceiving a relationship where none exists.

Scatterplot

A graph showing the relationship between two variables.

Regression Toward the Mean

Extreme scores tend to move closer to the average over time.

Experimental Methodology

Research that manipulates variables to determine cause-and-effect.

Experiment

A study in which one variable is manipulated to observe its effect on another.

Independent Variable (IV)

The variable that is manipulated.

Dependent Variable (DV)

The variable that is measured.

Confounding Variable

An uncontrolled factor that could affect results.

Experimental Group

Receives the treatment.

Control Group

Does not receive the treatment. (often receives a placebo)

Random Assignment

Participants are randomly placed into groups.

Single-Blind Procedure

Participants do not know which group they are in.

Double-Blind Procedure

Neither participants nor researchers know group assignments.

Placebo

An inactive substance or treatment.

Placebo Effect

Changes in behavior caused by expectations rather than the treatment itself.

Validity

The extent to which a study measures what it claims to measure.

Institutional Review Board (IRB)

Committee that reviews research proposals for ethical concerns.

Informed Consent

Participants are informed about the study and agree to participate.

Informed Assent

Agreement from minors, with parental consent.

Protect from Harm

Participants should not experience physical or psychological harm.

Confidentiality

Personal data must be kept private.

Debriefing

Explaining the true purpose of a study after participation.

Research Confederates

Individuals who are part of the research team but pretend to be participants.

Quantitative Research

Data expressed in numbers.

Qualitative Research

Data expressed in words or descriptions.

Likert Scales

Rating scales (e.g., strongly agree → strongly disagree).

Descriptive Statistics

Summarize and describe data.

Mean

Average score.

Median

Middle score.

Mode

Most frequent score.

Range

Highest score minus lowest score.

Standard Deviation

Measures how spread out scores are from the mean.

Histogram

Bar graph showing distribution of data.

Skewed Distribution

Data is not symmetrical.

Normal Curve

Bell-shaped, symmetrical distribution.

Percentile Rank

Percentage of scores below a given score.

Inferential Statistics

Determine whether results can be generalized to the population.

Statistical Significance

Likelihood that results occurred by chance.

Effect Size

Measures the strength of a relationship or treatment effect.