- Case study: a descriptive research strategy in which one person is studied in great depth
- Control condition: the condition of an experiment that contrasts with the experimental condition and serves as a comparison for evaluating the effect of the treatment.
- Correlation: a statistical measure that indicates the extent to which two factors vary together and thus how well one factor can be predicted from the other. Correlations can be positive or negative.
- Critical thinking: thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions.
- Culture: the enduring behaviors, ideas, attitudes, and traditions shared by a large group of people and transmitted from one generation to the next.
- Dependent variable: the factor being measured by the investigator.
- Double-blind procedure: a control procedure in which neither the experimenter nor the research subjects are aware of which condition is in effect. It is used to prevent experimenters' and subjects' expectations from influencing the results of an experiment.
- Experiment: a research strategy in which a researcher directly manipulates one or more factors (independent variables) in order to observe their effect on some behavior or mental process (the dependent variables; experiments therefore make it possible to establish cause-and-effect relationships.
- Experimental condition: the condition of an experiment that exposes participants to the treatment, that is, to one version of the independent variable.
- False consensus effect: is the tendency to overestimate the extent to which others share our beliefs and behaviors.
- Hindsight bias: the tendency to believe, after learning an outcome, that one would have foreseen it. (Also known as the I-knew-it-all along phenomenon.)
- Hypothesis: a testable prediction
- Illusory correlation: the false perception of a relationship between two events when none exists.
- Independent variable: the factor being manipulated and tested by the investigator.
- Mean: the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores.
- Medians: the middle score in a distribution; half the scores are above it and half are below it.
- Mode: the most frequently occurring score in a distribution; it is the simplest measure of central tendency to determine.
- Naturalistic observation: involves observing and recording behavior in naturally occurring situations without trying to manipulate or control the situation.
- Operational definitions: precise statements of the procedures (operations) used to define independent and dependent variables.
- Placebo: an inert substance or condition that is administered as a test of whether an experimental subjects who mistakenly thinks a treatment
- Placebo effect: experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which is assumed to be an active agent.
- Population: all the cases in a group, from which samples may be drawn for a study.
- Random assignment: the procedure of assigning subjects to the experimental and control conditions by chance in order to minimize preexisting differences between the groups.
- Random sample: a sample that fairly represents a population because each member has an equal chance of inclusion.
- Range: a measure of variation computed as the difference between the highest and lowest scores in a distribution.
- Replication: repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances
- Scatterplot: a depiction of the relationship between two variables by means of a graphed cluster of dots.
- Standard deviation: the average amount by which the scores in a distribution deviate around the mean. Because it is based on every score in the distribution
- Statistical significance: a statistical statement of how likely it is that an obtained result occurred by chance.
- Survey: a technique for ascertaining the self-reported attitudes or behaviors of people, usually by questioning a representative, random sample of them.
- Theory: an explanation using an integrated set of principles that organizes and predicts observations.