AP PYSCHOLOGVY UNIT 0

Unit 0 AP Psychology Study Guide

Terms and Definitions

• Critical thinking → Thinking that evaluates evidence and assumptions instead of blindly accepting arguments.

• Cognitive biases → Systematic errors in thinking that affect decisions and judgments.

• Hindsight bias → The tendency to believe, after learning an outcome, that one would have predicted it (“I knew it all along”).

• Overconfidence → Tendency to overestimate the accuracy of one’s knowledge or judgments.

• Scientific Method → A systematic process for asking questions, forming hypotheses, conducting research, analyzing data, and drawing conclusions.

• Peer review → Evaluation of research by experts in the field before publication to ensure quality and accuracy.

• Hypothesis → A testable prediction about the relationship between variables.

• Operational definition → A precise description of how a variable will be measured or manipulated in a study.

• Social desirability bias → Tendency of participants to answer questions in a way that will be viewed favorably by others.

• Self-report bias → Inaccuracy in responses due to memory errors, exaggeration, or desire to look good.

• Random sample → A subset of the population chosen so that every member has an equal chance of being selected.

• Sampling bias → A sample that does not accurately represent the population.

• Population → The entire group of individuals a study aims to describe or analyze.

• Correlation → A measure of the relationship between two variables, indicating how one predicts the other.

• Correlation coefficient (r) → A numerical value from −1 to +1 representing the strength and direction of a correlation.

• Variables → Factors that can change or vary in a study.

• Illusory correlation → Perceiving a relationship between variables when none exists.

• Scatterplot → A graph of points representing the values of two variables to show their relationship.

• Regression towards the mean → The tendency for extreme scores to move closer to the average upon retesting.

• Experimental group → The group in an experiment that receives the treatment or manipulation.

• Control group → The group that does not receive the treatment, serving as a baseline for comparison.

• Random assignment → Placing participants into experimental and control groups by chance to reduce bias.

• Placebo effect → Change resulting from participants’ expectations rather than the actual treatment.

• Single-blind procedure → Only participants do not know whether they are in the experimental or control group, reducing bias.

• Double-blind procedure → Both participants and researchers do not know group assignments, reducing bias from both sides.

• Independent variable (IV) → The variable that is manipulated in an experiment.

• Dependent variable (DV) → The outcome variable that is measured to assess the effect of the IV.

• Confounding (3rd) variable → An uncontrolled factor that may influence the results of a study.

• Validity → The extent to which a test or study measures what it claims to measure.

• Research design → The overall strategy and structure used to conduct a study.

• Meta-analysis → A statistical technique combining results from multiple studies to find overall trends.

• Case study → Intensive examination of one person or small group; provides detailed information but limited generalizability.

• Naturalistic observation → Observing behavior in its natural environment without interference.

• Survey → Collecting self-reported data through questionnaires or interviews.

• Cross-sectional study → Compares different groups at a single point in time to identify patterns or differences.

• Longitudinal study → Follows the same participants over an extended period to observe changes and development.

• Experimental study → Manipulates an independent variable to observe causal effects on a dependent variable.

• Correlational study → Measures the relationship between two variables without manipulation; identifies associations but not causation.

• Descriptive statistics → Methods for organizing, summarizing, and describing data (mean, median, mode, etc.).

• Histogram → A bar graph representing the frequency of scores in intervals.

• Central tendency → A measure that represents the center or typical value of a dataset (mean, median, mode).

• Mean → Average score; sum of all scores divided by the number of scores.

• Median → Middle score in an ordered set of numbers.

• Mode → Most frequently occurring score in a dataset.

• Range → Difference between the highest and lowest scores.

• Standard deviation (SD) → A measure of how spread out scores are around the mean.

• Normal curve → Bell-shaped distribution of scores, where most fall near the mean.

• Statistically significant → Results unlikely to be due to chance (often p < .05).

• Informed consent → The process of providing participants with all relevant information about a study (purpose, procedures, risks, benefits) so they can voluntarily agree to participate.

Key Concepts

• Psychology is a science because it relies on systematic observation, experimentation, and analysis to understand behavior and mental processes.

• Replication ensures findings are reliable and not due to chance.

• Non-experimental methods include case studies, naturalistic observations, and surveys, each with specific strengths and limitations.

• Correlation indicates a relationship but does not prove causation. Positive correlations move together; negative correlations move oppositely.

• Correlational research cannot establish the direction of causation.

• In experiments, the independent variable is manipulated, and the dependent variable is measured.

• Research design depends on whether the goal is description, prediction, or explanation.

• Quantitative research involves numbers and statistical analysis; qualitative research involves descriptive data.

• Ethics in research ensures participant safety, informed consent, confidentiality, and humane treatment of animals.

• Statistical reasoning organizes data, identifies patterns, and determines if results are meaningful.

• Mean, median, and mode measure central tendency in different ways and provide complementary insights.

Ethics in Research

• Informed consent → Participants must fully understand the study and voluntarily agree to participate.

• Protection from harm → Participants should not experience physical or psychological harm.

• Confidentiality → Participants’ data must be kept private.

• Debriefing → Explaining the purpose and results of the study after participation.

• Animal research guidelines → Clear purpose, humane care, minimize suffering.