Statistics — Page 44
Explore statistical methods, their assumptions, interpretation and limitations.
Research field
Method family
Ordinal Logistic Regression
Ordinal logistic regression — most commonly the proportional-odds model — estimates the relationship between one or more predictors and an ordered categorical outcome (e.g., Likert scales, disease severity grades, educational attainment lev...
Ordinal McDonald's omega
Ordinal McDonald's omega is a reliability coefficient designed for Likert-type and other ordinal rating scales. Unlike Cronbach's alpha, it bases its calculation on polychoric correlations among items — capturing the true latent relationshi...
Ordinal Measurement Invariance
Ordinal measurement invariance testing evaluates whether a multi-group confirmatory factor model holds equivalent measurement properties across groups when scale items are ordinal — such as Likert-type response scales. It uses polychoric co...
Ordinal Nomological Validity
Ordinal nomological validity examines whether a construct measured with ordinal items (e.g., Likert-type scales) behaves in theoretically predicted ways within a nomological network — a web of expected relationships with other constructs an...
Ordinal Rasch Model
The ordinal Rasch model extends the dichotomous Rasch framework to items with ordered response categories such as Likert-type scales. It places both persons and items on a shared interval-level metric, enabling principled measurement from o...
Ordinal Regression
Ordinal logistic regression models an ordered categorical outcome — such as a Likert rating, a satisfaction level, or an education tier — as a function of predictors. It is the ordinal extension of logistic regression, developed in standard...
Ordinal Reliability Analysis
Ordinal reliability analysis estimates the internal consistency of scales whose items are measured on ordered-category (Likert-type) response formats. By basing computations on polychoric correlations rather than Pearson correlations, it co...
Ordinal Scale Development
Ordinal scale development is the systematic construction and validation of multi-item measurement instruments whose response options form an ordered but not necessarily equal-interval sequence — most commonly Likert-type formats (e.g., 1 =...
Ordinal Test-Retest Reliability
Ordinal test-retest reliability quantifies how consistently an ordinal measurement instrument — such as a Likert-scale questionnaire or a rating tool — ranks or scores the same participants across two separate administrations separated by a...
Ordinary Kriging
Ordinary Kriging (OK) is the standard geostatistical method for interpolating a continuous spatial variable at unsampled locations. It derives optimal, unbiased weights from the spatial covariance structure of the data, making it the Best L...
Ordinary Least Squares
Ordinary Least Squares (OLS) is the canonical method for estimating the parameters of a linear regression model by minimizing the sum of squared differences between observed and predicted values. First published by Adrien-Marie Legendre in...
Organizational Identification Scale
The Organizational Identification Scale is Mael and Ashforth's widely used measure of the extent to which people define themselves in terms of their organizational membership. It rests on the social-identity reformulation of identification...
Overlapping Generations Model
The Overlapping Generations Model, pioneered by Paul Samuelson in 1958 and extended by Peter Diamond in 1965, is a macroeconomic framework where successive generations of individuals live for finite periods and coexist at any point in time....
PANIC
PANIC (Panel Analysis of Non-stationarity in Idiosyncratic and Common Components) is a second-generation panel unit root test introduced by Bai and Ng (2004). It decomposes each panel series into common factors and idiosyncratic components,...
PCM / GPCM
The Partial Credit Model is an extension of the Rasch measurement framework designed for ordered polytomous items — items whose responses fall into more than two ordered categories, such as partial-credit tasks in performance assessment or...
PIMS Profit Impact of Market Strategy Analysis
PIMS (Profit Impact of Market Strategy) analysis searches a large, multi-industry database of business units for the general empirical relationships that link strategy and market conditions to profitability. Originating in General Electric'...
PROMIS Physical Function Item Bank
The PROMIS Physical Function item bank is a large, item-response-theory-calibrated collection of self-reported questions about physical functioning and mobility, developed under the United States National Institutes of Health Patient-Report...
Page's L Test
Page's L test is a nonparametric hypothesis test designed for repeated-measures (randomized complete block) designs in which the researcher has a specific, pre-stated ordering hypothesis across k ≥ 3 conditions. Introduced by Ellis Batten P...
Paired samples t-test
The paired samples t-test is a parametric hypothesis test that compares the means of two related measurements from the same subjects or matched pairs to determine whether the average difference is significantly different from zero. It lever...
Paired t-test
The paired samples t-test is a parametric hypothesis test that compares two measurements taken on the same subjects — such as a before and after reading — to decide whether the average change differs from zero. It rests on the t-distributio...
Pairs Trading
Pairs trading is a quantitative trading strategy that takes a long-short position on two cointegrated assets when the gap (spread) between their prices shows mean reversion. It was popularised as a relative-value arbitrage rule by Gatev, Go...
Panel ADF Unit Root Test
The Panel Augmented Dickey-Fuller (Panel ADF) unit root test extends the classical ADF framework to panel datasets. By pooling information across cross-sectional units it achieves substantially higher power than single-series ADF tests, all...
Panel AR model
The Panel AR model extends the classical univariate autoregressive model to panel data, capturing how each unit's own past values predict its current value while controlling for unobserved individual heterogeneity through fixed or random ef...
Panel ARDL Bounds Test
The Panel ARDL Bounds Test extends the Pesaran, Shin and Smith (2001) bounds testing procedure to panel data, allowing researchers to test for long-run cointegrating relationships between variables without requiring all series to be integra...