Statistics
Explore statistical methods, their assumptions, interpretation and limitations.
Research field
Method family
1RM Estimation
One-repetition maximum (1RM) estimation is a method to predict an athlete's maximum strength in a given lift without performing an actual maximal single repetition. Developed systematically by Matt Brzycki (1993) and refined by numerous res...
2PL IRT
The two-parameter logistic item response model, formalised by Frederic Lord (1980), describes the probability that a respondent answers a binary test item correctly as a smooth S-shaped function of the respondent's latent ability. By estima...
3PL IRT
The three-parameter logistic (3PL) model, introduced by Allan Birnbaum in 1968, is an item response theory model that describes the probability of a correct response to a binary test item as a function of three item-level parameters — diffi...
Abusive Supervision Scale
The Abusive Supervision Scale measures subordinates' perceptions of the extent to which their supervisors engage in sustained displays of hostile verbal and nonverbal behaviors, excluding physical contact. Bennett Tepper introduced both the...
Acute-Chronic Workload Ratio
The acute-chronic workload ratio (ACWR) is the ratio of acute training load (typically the past 1 week) to chronic training load (typically the rolling 4-week average). Formalized by Tim Gabbett (2016), ACWR is a widely adopted metric for p...
Allostatic Load Index
The allostatic load index quantifies the cumulative biological cost of chronic stress by summing dysregulation across multiple physiological systems. McEwen and Stellar introduced 'allostatic load' in 1993 to name the wear and tear the body...
Anti-Immigrant Prejudice Scale
The Anti-Immigrant Prejudice Scale, developed by Thomas Pettigrew and Roel Meertens in 1995, measures prejudice toward immigrants along two dimensions: blatant prejudice, which is hot, close, and direct, expressing open rejection and percei...
Attitudes to Aging Questionnaire
The Attitudes to Ageing Questionnaire (AAQ) measures how older adults perceive their own experience of growing older, capturing self-directed attitudes rather than younger people's stereotypes of the old. Developed by Ken Laidlaw, Mick Powe...
AttrakDiff/UEQ
AttrakDiff and the User Experience Questionnaire (UEQ) are assessment instruments for measuring user experience across multiple dimensions. AttrakDiff, developed by Marc Hassenzahl, evaluates the tension between pragmatic quality (functiona...
Authentic Leadership Questionnaire
The Authentic Leadership Questionnaire (ALQ) is the dominant instrument for measuring authentic leadership, a positive leadership construct developed in the mid-2000s by Bruce Avolio, William Gardner, Fred Luthans, and colleagues. Authentic...
BIS/BAS Scales
The BIS/BAS Scales, developed by Carver and White in 1994, are self-report measures of two fundamental motivational systems proposed by Gray's reinforcement sensitivity theory. The Behavioral Inhibition System (BIS) governs sensitivity to p...
Banister TRIMP
The Training Impulse (TRIMP) model, developed by Eric Banister and colleagues (1975), quantifies the physiological stimulus of a training session by combining duration and intensity. The Banister fitness-fatigue model proposes that training...
Bifactor Model
The bifactor measurement model specifies that every indicator loads simultaneously on a single general factor and on one of several specific (group) factors. Formally introduced by Holzinger and Swineford in 1937 and brought into mainstream...
Blatant Dehumanization Scale
The Blatant Dehumanization Scale, also called the Ascent of Man measure, captures the willingness to overtly deny full humanity to an out-group. Developed by Nour Kteily, Emile Bruneau, Adam Waytz, and Sarah Cotterill in 2015, it uses the i...
CASP-19 Quality of Life Scale
The CASP-19 is a 19-item self-report measure of quality of life designed specifically for people in early old age, grounded in a theory of human need rather than in health or functional status. Developed by Martin Hyde, Richard Wiggins, Pau...
CAT Generalizability Theory
Generalizability theory (G-theory) applied to computerized adaptive testing (CAT) evaluates the dependability of adaptive test scores by decomposing score variance across measurement facets such as persons, items, and occasions. Unlike clas...
CAT McDonald's Omega
McDonald's omega adapted for computerized adaptive testing (CAT) quantifies the reliability of ability or trait estimates when different examinees answer different subsets of items. Unlike Cronbach's alpha, omega is grounded in a factor mod...
CAT Scale Development
Computerized adaptive test (CAT) scale development is the process of constructing, calibrating, and validating a large item bank such that the assessment algorithm can select items tailored to each examinee's estimated ability or trait leve...
CAT-DIF
CAT-DIF identifies items in a computerized adaptive test that behave differently across demographic or group subpopulations after controlling for overall ability. Because adaptive algorithms select items non-randomly based on each examinee'...
CHIEF Environmental Barriers
The Craig Hospital Inventory of Environmental Factors, known as CHIEF, is a self-report instrument that quantifies the environmental barriers people with disabilities encounter in daily life. Developed by Whiteneck and colleagues in 2004, i...
Capture-Recapture
Capture-recapture (also known as mark-recapture) is a statistical method for estimating the size of an unknown population by sampling it twice and tracking which individuals appear in both samples. Formally systematized for closed animal po...
Card Sorting
Card Sorting is a participatory design technique where users organize content items (represented on cards) into logical groups and categories. Used primarily for information architecture design, card sorting reveals how users naturally thin...
Caregiver Strain Index
The Caregiver Strain Index (CSI) is a brief, thirteen-item yes/no screening tool that measures the strain experienced by informal caregivers of older adults. Developed and validated by Betsy Robinson in 1983, it was designed to be a quick,...
Case-Cohort Design
Case-cohort design is an epidemiological study design developed by Prentice (1986) that efficiently combines features of case-control and cohort studies. Researchers enroll an entire cohort, follow it for outcomes, then measure exposures on...