Statistics — Page 2
Explore statistical methods, their assumptions, interpretation and limitations.
Research field
Method family
Construct Validity
Construct validity is the degree to which a test or scale actually measures the theoretical construct it is intended to measure. Introduced by Cronbach and Meehl in 1955, it is the central validity concern in psychological and educational m...
Content Validity
Content validity is evidence that a measurement instrument adequately samples the full domain of the construct it is intended to measure. It is established through systematic expert review and quantified with indices such as Lawshe's Conten...
Convergent Validity
Convergent validity is the degree to which multiple indicators that are theoretically expected to measure the same construct actually correlate with one another. It is one of the two complementary forms of construct validity identified by C...
DINA Model
The DINA Model (Deterministic Inputs, Noisy Outputs) is a cognitive diagnostic model developed by Junker and Sijtsma (2001) that classifies examinees into latent skill classes based on their item response patterns. DINA assumes a determinis...
DINO Model
The DINO Model (Deterministic Inputs, Noisy Outputs—Disjunctive) is a cognitive diagnostic model that relaxes DINA's conjunctive (AND) skill requirement logic. DINO assumes an examinee only needs to master one of multiple possible skill pat...
Dichotic Listening
The Dichotic Listening Task is an auditory measure of selective attention and hemispheric lateralization. Different speech stimuli (words, digits, or syllables) are presented simultaneously to each ear via headphones. Participants attend to...
Dictator Game
The Dictator Game is a simple economic decision task measuring generosity and prosocial behavior. One player (dictator) receives money and unilaterally decides how to allocate it between themselves and an anonymous second player (recipient)...
Differential Item Functioning
Differential item functioning identifies test or survey items that behave differently for examinees from different groups — such as gender, ethnicity, or language background — after controlling for the underlying ability or trait being meas...
Discriminant Validity
Discriminant validity is evidence that a latent construct is empirically distinct from other constructs it should differ from. Originating in Campbell and Fiske's multitrait-multimethod framework (1959), it is a core component of construct...
Drift Diffusion Model
The Drift Diffusion Model (DDM) is a mathematical framework for understanding rapid binary decision-making by modeling the accumulation of evidence over time as a random walk with drift. Developed by Roger Ratcliff in the 1970s, it predicts...
Experiences in Close Relationships Scale
The Experiences in Close Relationships (ECR) scale, developed by Brennan, Clark, and Shaver in 1998, is the most widely used self-report measure of adult romantic attachment. The authors factor-analyzed essentially all existing English-lang...
Eye-Tracking Analysis
Eye-tracking analysis is a method for recording and quantifying eye movements and gaze patterns during visual tasks, providing direct measures of visual attention, comprehension, and cognitive processing. Advancing from mechanical devices t...
Fear Conditioning
Fear conditioning is a classical (Pavlovian) learning paradigm in which a neutral stimulus (conditioned stimulus, CS—e.g., a tone or image) is repeatedly paired with an aversive outcome (unconditioned stimulus, US—e.g., mild electric shock...
Fuzzy-Set Qualitative Comparative Analysis
Fuzzy-Set Qualitative Comparative Analysis (fsQCA) is a set-theoretic method developed by Charles Ragin in the early 2000s that combines the configurational logic of qualitative case studies with the mathematical rigor of fuzzy sets. It bri...
G-Theory
Generalizability Theory, developed by Lee J. Cronbach and colleagues in the 1960s and formalised by Brennan (2001), is an ANOVA-based framework that extends Classical Test Theory by decomposing observed score variance into multiple, separat...
Generalizability Theory
Generalizability Theory is a psychometric framework that decomposes observed score variance into multiple sources — persons, items, raters, occasions, and their interactions — using analysis of variance. It replaces the single reliability c...
Implicit Association Test
The Implicit Association Test (IAT) is a computerized measure designed to detect automatic associations between concepts in memory, such as implicit attitudes toward social groups or implicit self-concepts. Introduced by Greenwald, McGhee,...
Implicit Theories Measure
The implicit theories measure, developed by Dweck, Chiu, and Hong in 1995, assesses people's lay beliefs about whether human attributes are fixed or malleable -- the distinction popularized as fixed versus growth mindset. Respondents rate a...
Iowa Gambling Task
The Iowa Gambling Task (IGT) is a laboratory analog of real-world decision-making that measures how individuals make risky choices when outcomes are uncertain. Participants select cards from four decks, each offering different patterns of r...
Item Analysis
Item analysis is the foundational psychometric procedure for evaluating the quality of individual test or scale items within the Classical Test Theory (CTT) framework, as systematised by Allen and Yen (1979) and Crocker and Algina (1986). I...
Item Response Theory
Item response theory models the probability that a respondent answers an item correctly (or endorses it) as a function of the respondent's latent trait level and the item's own statistical properties — difficulty, discrimination, and guessi...
Lexical Decision Task
The Lexical Decision Task is a computerized measure of word recognition and semantic processing. Participants judge whether letter strings are real words or nonwords (pronounceable but meaningless letter combinations). Response times and ac...
Longitudinal Construct Validity
Longitudinal construct validity evaluates whether a psychological scale measures the same latent construct in the same way across multiple time points. It is tested by progressively constraining a confirmatory factor model across waves and...
Longitudinal DIF
Longitudinal differential item functioning detects whether individual test or scale items behave differently across measurement occasions for the same respondents. It extends standard DIF methodology to repeated-measures designs, ensuring t...