AP Psychology Unit 0 Terms


  1. Experimental vs. Non-Experimental:

    • Experimental: Manipulates an independent variable to determine cause-and-effect relationships.

    • Non-Experimental: Observes and describes phenomena without manipulation (e.g., correlational studies).

  2. Independent Variable (IV):

    • The factor manipulated by the researcher.

  3. Dependent Variable (DV):

    • The outcome measured to assess the effect of the IV.

  4. Confounding Variables:

    • Extraneous variables that can affect the DV.

  5. Random Assignment:

    • Assigning participants to groups randomly to minimize bias.

  6. Population:

    • The entire group being studied.

  7. Sample:

    • A subset of the population selected for research.

  8. Random Sampling:

    • Each member of the population has an equal chance of being selected.

  9. Representative Samples:

    • Samples that accurately reflect the population's characteristics.

  10. Convenience Samples:

    • Samples chosen based on ease of access, risking bias.

  11. Sampling Bias:

    • When a sample does not accurately represent the population.

  12. Generalizability:

    • The applicability of findings to a broader population.

  13. Experimental Group:

    • The group that receives the treatment.

  14. Control Group:

    • The group that does not receive the treatment, serving as a comparison.

  15. Placebo Group:

    • A group receiving a placebo to control for expectations.

  16. Placebo Effect:

    • Improvement due to belief in treatment rather than the treatment itself.

  17. Single-Blind Procedure:

    • Participants do not know their group assignment.

  18. Double-Blind Procedure:

    • Neither participants nor researchers know group assignments.

  19. Experimenter Bias:

    • When researchers' expectations influence the outcome.

  20. Case Study:

    • An in-depth examination of a single subject or group.

  21. Correlation (Does Not Equal Causation):

    • Correlation does not imply one variable causes another.

  22. Positive Correlation:

    • Both variables move in the same direction.

  23. Negative Correlation:

    • One variable increases as the other decreases.

  24. Directionality Problem:

    • Uncertainty about which variable affects the other.

  25. Third-Variable Problem:

    • A confounding variable that influences both studied variables.

  26. Scatterplots:

    • Graphs showing the relationship between two variables.

  27. Correlation Coefficient:

    • A numerical value (ranging from -1 to +1) indicating strength and direction of a correlation.

  28. Quantitative Measures:

    • Numerical data (e.g., Likert scales).

  29. Qualitative Measures:

    • Descriptive data (e.g., structured interviews).

  30. Surveys:

    • Tools to gather information from large groups.

  31. Framing:

    • The way information is presented, influencing perceptions.

  32. Social Desirability Bias:

    • Tendency to respond in a way that will be viewed favorably by others.

  33. Self-Report Bias:

    • Inaccuracy in responses about oneself.

  34. Meta-Analysis:

    • A method that combines results from multiple studies.

  35. Naturalistic Observation:

    • Observing subjects in their natural environment.

  36. Hypothesis:

    • A testable prediction about the relationship between variables.

  37. Falsifiability:

    • The ability to be disproven; a key criterion for scientific hypotheses.

  38. Operational Definitions:

    • Specific definitions of variables used in a study.

  39. Replication and Peer Review:

    • The process of repeating studies and evaluating by experts to ensure validity.

  40. Ethical Guidelines:

    • Principles guiding researchers to ensure participant welfare.

  41. Institutional Review Board (IRB):

    • A committee that reviews research proposals for ethical considerations.

  42. Informed Consent:

    • Participants are informed about the study and agree to participate.

  43. Informed Assent:

    • Agreement from participants (often minors) who are informed but may not fully understand.

  44. Protection from Harm:

    • Ensuring that participants are not exposed to risks beyond minimal discomfort.

  45. Confidentiality of Participants:

    • Keeping participants' information private.

  46. Minimal Deception:

    • Using deception only when necessary and justified.

  47. Confederates:

    • People who act as participants but are actually part of the experiment.

  48. Debriefing:

    • Explaining the study’s purpose and methods to participants after completion.

  49. Central Tendency:

    • A statistical measure that identifies a single score as representative of an entire distribution (mean, median, mode).

  50. Measures of Variation:

    • Statistics that describe the spread of data (e.g., range, standard deviation).

  51. Normal Curve:

    • A bell-shaped curve representing a normal distribution of data; 68% falls within one standard deviation.

  52. Positive and Negative Skews:

    • Positive Skew: A distribution with a long tail on the right.

    • Negative Skew: A distribution with a long tail on the left.

  53. Bimodal Distributions:

    • Distributions with two modes or peaks.

  54. Regression Toward the Mean:

    • The tendency for extreme scores to fall back toward the average over time.

  55. Statistical Significance:

    • The likelihood that a result is not due to chance, often assessed with p-values.

  56. Effect Sizes:

    • A measure of the strength of the relationship between two variables.

  57. Cognitive Biases:

    • Systematic patterns of deviation from norm or rationality in judgment.

    • Confirmation Bias: Tendency to search for, interpret, and remember information that confirms one’s preexisting beliefs.

    • Hindsight Bias: The "I-knew-it-all-along" effect; the tendency to see events as having been predictable after they have already occurred.

    • Overconfidence: Excessive confidence in one’s own answers, beliefs, or judgments.