AP Psychology Unit 0 Critical Thinking and Research Methods Vocab

Comprehensive vocabulary terms and definitions for AP Psychology Unit 0, focusing on critical thinking, research design, and statistical analysis.

Critical Thinking

a form of directed, problem-focused thinking in which the individual tests ideas or possible solutions for errors or drawbacks. It is essential to such activities as examining the validity of a hypothesis or interpreting the meaning of research results.

Hindsight Bias

the tendency, after an event has occurred, to overestimate the extent to which the outcome could have been foreseen

Peer Reviews

the evaluation of scientific or academic work, such as research or articles submitted to journals for publication, by other qualified professionals practicing in the same field.

Theory

a principle or body of interrelated principles that purports to explain or predict a number of interrelated phenomena.

Hypothesis

an empirically testable proposition about some fact, behavior, relationship, or the like, usually based on theory, that states an expected outcome resulting from specific conditions or assumptions.

Falsifiable

the condition of admitting falsification: the logical possibility that an assertion, hypothesis, or theory can be shown to be false by an observation or experiment.

Operational Definition

a description of something in terms of the operations (procedures, actions, or processes) by which it could be observed and measured.

Replication

the repetition of an original experiment or research study to verify or bolster confidence in its results.

Case Study

an in-depth investigation of a single individual, family, event, or other entity

Naturalist Observation

data collection in a field setting, without laboratory controls or manipulation of variables.

Survey

a study in which a group of participants is selected from a population and data about or opinions from those participants are collected, measured, and analyzed.

Social Desirability Bias

the bias or tendency of individuals to present themselves in a manner that will be viewed favorably by others.

Self-Report Bias

a methodological problem that arises when researchers rely on asking people to describe their thoughts, feelings, or behaviors rather than measuring these directly and objectively.

Sampling Bias

a systematic and directional error involved in the choice of units, cases, or participants from a larger group for study.

Random Sample

a process for selecting a sample of study participants from a larger potential group of eligible individuals, such that each person has the same fixed probability of being included in the sample and some chance procedure is used to determine who specifically is chosen.

Population

the total number of individuals (humans or other organisms) in a given geographical area.

Correlation

the degree of a relationship (usually linear) between two variables, which may be quantified as a correlation coefficient.

Correlation Coefficient

a numerical index reflecting the degree of linear relationship between two variables.

Variable

a condition in an experiment or a characteristic of an entity, person, or object that can take on different categories, levels, or values and that can be quantified (measured).

Scatterplot

a graphical representation of the relationship between two continuously measured variables in which one variable is arrayed on each axis and a dot or other symbol is placed at each point where the values of the variables intersect.

Illusory Correlation

the appearance of a relationship that in reality does not exist.

Regression toward the mean

the tendency for extremely high or extremely low scores to become more moderate (i.e., closer to the mean) upon retesting over time.

Experiment

a series of observations conducted under controlled conditions to study a relationship with the purpose of drawing causal inferences about that relationship.

Experimental Group

a group of participants in a research study who are exposed to a particular manipulation of the independent variable

Control Group

a comparison group in a study whose members receive either no intervention at all or some established intervention.

Random Assignment

in experimental design, the assignment of participants or units to the different conditions of an experiment entirely at random, so that each unit or participant has an equal likelihood of being assigned to any particular condition.

Single-Blind Procedure

an experiment where participants don’t know whether they’re receiving the real treatment or a placebo, but the researchers running the study do know.

Placebo Effect

a clinically significant response to a therapeutically inert substance or nonspecific treatment (placebo), deriving from the recipient’s expectations or beliefs regarding the intervention.

Independent Variable

the variable in an experiment that is specifically manipulated or is observed to occur before the dependent, or outcome, variable, in order to assess its effect or influence.

Confounding Variable

an unmeasured third variable that influences, or “confounds,” the relationship between an independent and a dependent variable by suggesting the presence of a spurious correlation.

Experimenter Bias

any systematic errors in the research process or the interpretation of its results that are attributable to a researcher’s behavior, preconceived beliefs, expectancies, or desires about results.

Dependent Variable

the outcome that is observed to occur or change after the occurrence or variation of the independent variable in an experiment, or the effect that one wants to predict or explain in correlational research.

Validity

the degree to which empirical evidence and theoretical rationales support the adequacy and appropriateness of conclusions drawn from some form of assessment.

Qualitative Research

a method of research that produces descriptive (non-numerical) data, such as observations of behavior or personal accounts of experiences.

Informed Consent

a person’s voluntary agreement to participate in a procedure on the basis of their understanding of its nature, its potential benefits and possible risks, and available alternatives.

Debriefing

the process of giving participants in a completed research project a fuller explanation of the study in which they participated than was possible before or during the research.

Descriptive Statistics

procedures for depicting the main aspects of sample data, without necessarily inferring to a larger population.

Histogram

a graphical depiction of continuous data using bars of varying height, similar to a bar graph but with blocks on the x-axis adjoining one another so as to denote their continuous nature.

Mode

a characteristic manner of behavior or way of doing things, as in a technique.

Mean

the numerical average of a set of scores, computed as the sum of all scores divided by the number of scores.

Median

the midpoint in a distribution, that is, the score or value that divides it into two equal-sized halves.

Percentile Rank

The percentage of scores in a distribution that fall at or below a particular individual’s score

Skewed Distribution

a set of data that clusters unevenly to one side rather than forming the familiar bell-shaped curve.

Range

a measure of dispersion obtained by subtracting the lowest score in a distribution from the highest score.

Standard Deviation

a measure of the variability of a set of scores or values within a group, indicating how narrowly or broadly they deviate from the mean.

Normal Curve

a continuous probability distribution for a real-valued random variable.

Inferential Statistics

a broad class of statistical techniques that allow inferences about characteristics of a population to be drawn from a sample of data from that population while controlling (at least partially) the extent to which errors of inference may be made.

Meta-Analysis

a quantitative technique for synthesizing the results of multiple studies of a phenomenon into a single result by combining the effect size estimates from each study into a single estimate of the combined effect size or into a distribution of effect sizes.

Statistical Significance

the degree to which a research outcome cannot reasonably be attributed to the operation of chance or random factors.

Effect Size

any of various measures of the magnitude or meaningfulness of a relationship between two variables