AP Psychology Module 0 Key Terms

Critical Thinking: Analyzing information objectively to make reasoned judgments.
Hindsight Bias: Believing, after an event, that the outcome was predictable.
Peer Reviewers: Experts who evaluate research before publication.
Theory: A well-substantiated explanation of some aspect of the natural world.
Hypothesis: A testable prediction about the relationship between variables.
Falsifiable: Capable of being proven false by evidence.
Operational Definition: A clear, measurable definition of a variable for research.
Replication: Repeating a study to confirm its results.

Case Study: An in-depth analysis of an individual or group.
Naturalistic Observation: Observing behavior in its natural environment without interference.
Survey (correlational study): Collecting self-reported data to find relationships between variables.

Social Desirability Bias: Responding in a way that will be viewed favorably by others.
Self-Report Bias: Distortion in data due to inaccurate or dishonest participant responses.
Sampling Bias: When a sample is not representative of the population.
Random Sample: A sample chosen so every member of the population has an equal chance to be included.
Population: The entire group being studied.
Correlation: A measure of how two variables change together.
Correlation Coefficient: A numerical value indicating the strength and direction of a correlation.
Variable: Any factor that can vary or change in a study.
Scatterplot: A graph showing the relationship between two variables.

Experiment: A study that tests cause-and-effect by manipulating variables.
Experimental Group: The group receiving the treatment or intervention.
Control Group: The group not receiving the treatment, used for comparison.
Random Assignment: Assigning participants to groups by chance to reduce bias.
Single Blind Procedure: Participants don’t know which group they are in.
Double Blind Procedure: Neither participants nor experimenters know group assignments.
Placebo Effect: Improvement due to belief in treatment, not the treatment itself.
Independent Variable: The variable manipulated by the researcher.
Confounding Variable: An outside factor that may affect the results.
Experimenter Bias: When researchers' expectations influence the outcome.
Dependent Variable: The outcome measured in a study.

Quantitative Research: Research based on numerical data.
Qualitative Research: Research based on descriptive, non-numerical data.
Informed Consent: Participants’ agreement to take part after being informed of risks.
Debriefing: Explaining the study’s purpose and procedures after participation.
Illusory Correlations: Perceiving a relationship that doesn’t actually exist.
Regression toward the Mean: Extreme scores tend to move closer to the average on retesting.
Validity: The extent to which a test measures what it claims to measure.
Descriptive Statistics: Numbers that summarize data features.
Histogram: A bar graph showing frequency distribution of data.
Mode: The most frequently occurring value in a data set.
Mean: The average of all data points.
Median: The middle value when data is ordered.
Percentile Rank: The percentage of scores below a given score.
Skewed Distribution: Data that is asymmetrically distributed.
Range: The difference between the highest and lowest values.
Standard Deviation: A measure of how spread out data is around the mean.
Normal Curve: A bell-shaped frequency distribution that is symmetrical.
Inferential Statistics: Methods used to draw conclusions about a population from a sample.
Meta-Analysis: Combining results from multiple studies to find overall trends.
Statistical Significance: The likelihood that results are not due to chance.
Effect Size: A measure of the strength of a relationship or treatment effect.