Chapter 1 - AP PSYCH Vocabulary

Critical Thinking

The ability to analyze, evaluate, and interpret information logically & objectively to make well-reasoned judgments & decisions.

Hindsight Bias

The tendency to believe, after an outcome is known, that we “knew it all along” or could have predicted it.

Overconfidence

The tendency to overestimate the accuracy of our knowledge, judgments, or abilities.

Peer Reviewers

Experts in a field who evaluate research before it’s published to check for accuracy, quality, and validity

Theory

A well-tested explanation that organizes observations & predicts future behavior or events

Hypothesis

A testable prediction about the relationship between variables.

Falsifiable

Able to be tested and potentially proven false through evidence.

Operational Definition

A clear, specific explanation of how a variable is measured or defined in a study.

Replication

Repeating a research study to confirm its results & reliability.

Case Study

An in-depth study of one person or group to reveal universal principles.

Naturalistic Observation

Observing & recording behavior in it natural environment without interference.

Survey

A research method that collects self-reported data from people through questions or interviews.

Social Desirability Bias

The tendency for people to answer questions in a way that makes them look good rather than truthfully.

Self-Report Bias

Distortions in survey or interview responses caused by inaccurate, selective, or dishonest self-reporting.

Sampling Bias

An error that occurs when a sample doesn’t represent the population, leading to inaccurate results.

Random Sample

A sample in which every member of the population has an equal chance of being selected.

Population

The entire group of people a researcher wants to study & draw conclusions about.

Correlation

A measure of the relationship between two variables, showing how one changes with the other.

Correlation Coefficient

A numerical value (from -1.0 to +1.0) that shows the strength & direction of a relationship between two variables.

Variable

Any factor or characteristic that can change or vary in a study.

Scatterplot

A graph that shows the relationship between two variables using plotted points.

Illusory Correlation

The mistaken belief that two variables are related when no actual relationship exists.

Regression Toward The Mean

The tendency for extreme scores or events to move closer to the average when measured again.

Experiment

A research method where variables are manipulated to test cause-and-effect relationships.

Experimental Group

The group in an experiment that receives the treatment or manipulation being tested.

Control Group

The group in an experiment that does not receive the treatment; used for comparison with the experimental group.

Random Assignment

The process of assigning participants to experimental or control groups by chance, reducing bias and ensuring groups are comparable.

Single-Blind Procedure

An experimental design where participants do not know if they are in the experimental or control group, but researchers do.

Double-Blind Procedure

An experimental design where neither participants nor researchers know who is in the experimental or control group, reducing bias.

Placebo Effect

Improvement caused by the expectation of treatment rather than the treatment itself.

Independent Variable

The factor in an experiment that is manipulated to test its effect on the dependent variable.

Confounding Variable

An outside factor that could influence results and interfere with the relationship between the independent and dependent variables.

Experimenter Bias

An outside factor that could influence results and interfere with the relationship between the independent and dependent variables.

Dependent Variable

The factor in an experiment that is measured; it changes in response to the independent variable.

Validity

The extent to which a test or study measures what it is intended to measure.

Quantitative Research

Research that collects and analyzes numerical data to identify patterns, test relationships, or make predictions.

Qualitative Research

Research that explores behaviors, experiences, and meanings using non-numerical data like interviews or observations.

Informed Consent

An ethical principle requiring that participants are fully informed about a study’s purpose, procedures, risks, and rights before agreeing to take part.

Debriefing

The process of informing participants after a study about its true purpose, methods, and any deception used.

Descriptive Statistics

Methods used to organize, summarize, and present data (e.g., mean, median, mode, graphs).

Histogram

A bar graph that shows the frequency distribution of data, with bars representing ranges of values.

Mode

The most frequently occurring score or value in a data set.

Mean

The average of a data set, found by adding all values and dividing by the number of values.

Median

The middle score in a data set when values are arranged in order.

Percentile Rank

The percentage of scores in a distribution that fall at or below a particular score.

Skewed Distribution

A data distribution that is not symmetrical, where scores cluster toward one side with a long tail on the other.

Range

The difference between the highest and lowest scores in a data set.

Standard Deviation

A measure of how spread out scores are around the mean in a data set.

Normal Curve

A symmetrical, bell-shaped distribution where most scores cluster around the mean, with fewer at the extremes.

Inferential Statistics

Techniques that use sample data to make generalizations or predictions about a larger population.

Meta-Analysis

A statistical technique that combines results from many studies to identify overall trends or effects.

Statistical Significance

A measure of whether research results are likely due to chance or represent a real effect, often set at p < 0.05.

Effect Size

A measure of the strength or magnitude of a relationship or difference, showing how meaningful the results are.