AP SET key terms

The degree to which a test or study measures what it claims to measure, so that inferences drawn from scores are accurate and defensible for the intended purpose and population.

The consistency of a measurement across repeated administrations, parallel forms, or items, indicating how much of observed score variation reflects true differences rather than random error.

Evidence that a test actually captures the underlying theoretical trait it names, gathered through convergent, discriminant, factorial, and nomological analyses rather than surface plausibility.

An estimate of the typical spread of a person's scores around their true score if tested repeatedly, used to build confidence intervals around an observed score.

A precise statement of how a variable will be observed and measured in a particular study, converting abstract concepts into observable procedures that others could replicate.

A testable, falsifiable prediction about the relationship between variables, stated before data collection so that results can confirm or contradict it.

The statistical assumption that no effect or difference exists in the population; significance testing estimates how unlikely the observed data would be if this assumption held.

The probability of obtaining a result at least as extreme as the observed one, assuming the null hypothesis is true; it is not the probability that the null hypothesis is correct.

Rejecting a true null hypothesis, that is, reporting an effect that does not actually exist; its long-run rate is controlled by the chosen significance level alpha.

Failing to reject a false null hypothesis, missing a real effect; its probability beta is inversely related to statistical power and to sample size.

The probability that a study will detect an effect of a given size if that effect truly exists; low power raises the risk of false negatives and inflated effect estimates.

A standardized index of the magnitude of a difference or association, independent of sample size, allowing comparison across studies beyond mere statistical significance.

A symmetric bell-shaped probability curve defined by its mean and standard deviation, in which most cases cluster near the centre and extreme values become progressively rarer.

The summary of a distribution's typical value, usually reported as mean, median, or mode; the choice matters because each responds differently to skew and outliers.

The average distance of scores from the mean, computed as the square root of the variance; it expresses spread in the original units of the data.

Systematic distortion introduced when the selected sample differs from the target population in ways relevant to the variables studied, undermining the generalizability of findings.

Selecting participants so that every member of the population has an equal, independent chance of inclusion, which supports unbiased estimation and valid inferential statistics.

The extent to which findings can be generalized beyond the specific sample, setting, and procedures of a study to other people, places, and times.

The degree to which a study supports causal claims by ruling out alternative explanations such as confounding variables, selection effects, and maturation.

An extraneous factor that is associated with both the independent and dependent variables, creating a spurious relationship or obscuring a genuine one.

Participants who do not receive the treatment under study, providing a baseline against which the experimental group is compared to isolate the treatment's effect.

Allocating participants to conditions by chance so that groups are statistically equivalent at the outset, a key safeguard for causal inference in experiments.

A quantitative synthesis that pools effect sizes from multiple independent studies on the same question, increasing precision and revealing patterns across the literature.

A critical, organized survey of existing scholarship on a topic that identifies what is known, what is contested, and where the proposed research adds value.

An unanswered question or under-investigated area identified from prior work, which justifies the need for a new study and frames its contribution.

Presenting another person's words, ideas, data, or structure as one's own without adequate attribution, whether done deliberately or through careless citation.

A formal reference acknowledging the source of a specific idea, quotation, or datum, enabling readers to locate the original and verify the claim.

Restating a source's meaning in one's own words and sentence structure while retaining accurate attribution, rather than merely swapping synonyms in the original wording.

Pre-publication evaluation of a manuscript by independent experts who assess methodological soundness, significance, and ethical compliance before acceptance.

Principles governing responsible conduct in research, including informed consent, minimizing harm, confidentiality, honesty in reporting, and fair treatment of participants and collaborators.

Voluntary agreement to participate given after a person understands the study's purpose, procedures, risks, benefits, and right to withdraw without penalty.

The researcher's obligation to protect participants' identifiable information from unauthorized disclosure, often implemented through anonymization, secure storage, and restricted access.

An approach using interviews, observation, or document analysis to explore meanings, experiences, and processes in depth, typically reported through themes rather than statistics.

An approach that collects numerical data and applies statistical analysis to test hypotheses, estimate relationships, and generalize findings to defined populations.

Using multiple methods, data sources, investigators, or theories to examine the same phenomenon, strengthening confidence in findings by checking convergence and divergence.

A hierarchical classification of learning objectives from remembering and understanding through applying, analyzing, evaluating, and creating, used to align instruction with assessment.

Ongoing, low-stakes checks of learning used to adjust teaching and give feedback during instruction, as distinct from summative grading at the end of a unit.

Evaluation conducted at the end of an instructional period to judge achievement against standards, typically contributing to grades, certification, or placement decisions.

A specific, observable statement of what learners should know or be able to do by the end of a course or unit, forming the basis for aligned instruction and assessment.