Statistics — Page 48
Explore statistical methods, their assumptions, interpretation and limitations.
Research field
Method family
Particle Filter with Measurement Error
A particle filter with explicit measurement error is a Sequential Monte Carlo algorithm that tracks the hidden state of a nonlinear, non-Gaussian dynamic system while formally modelling noise in the observations. A population of weighted ra...
Particle Filter with Missing Data
A particle filter adapted for state-space models in which some observations are absent. The algorithm tracks a hidden state over time using a cloud of weighted random samples (particles); when a time step has no observed value, the weight-u...
Partisan Business Cycle Analysis
Partisan business cycle analysis tests whether left-wing and right-wing governments produce systematically different macroeconomic outcomes. Douglas Hibbs's 1977 partisan theory argued that because left and right parties represent constitue...
Partisan Social Identity Scale
The Partisan Social Identity Scale treats party identification as a social identity in the sense of Henri Tajfel rather than as a running tally of policy agreement. Building on Steven Greene's social-identity approach and crystallized in Hu...
Path Analysis
Path analysis tests a researcher-specified causal diagram among observed variables by decomposing their intercorrelations into direct effects, indirect (mediated) effects, and spurious associations. Developed by Sewall Wright in 1921, it is...
Peace Duration Analysis
Peace duration analysis applies survival (time-to-event) methods to study how long peace lasts after a conflict ends and what makes it endure or collapse. The unit is the post-conflict peace spell, observed from a settlement or cessation un...
Pearson Correlation
Pearson correlation measures the direction and strength of linear association between two variables. It is their covariance divided by the product of their standard deviations.
Perceptual and Preference Mapping
Perceptual and preference mapping is a family of multivariate techniques that simultaneously positions competing objects—brands, products, or stimuli—and respondent preferences within a common low-dimensional space. Introduced systematicall...
Permutation Test
The permutation test is a nonparametric resampling procedure that builds the sampling distribution of a test statistic directly from the data by repeatedly shuffling the group labels. Developed in the resampling tradition and treated system...
Person-Organization Fit
Person-organization (P-O) fit is the organizational-behavior construct describing the compatibility between an individual and the organization they work for, most often operationalized as the congruence between personal and organizational v...
Pesaran CD Test
The Pesaran CD test is a general diagnostic procedure for detecting cross-sectional dependence in panel data models. Developed by M. Hashem Pesaran (2021), it is applicable to both balanced and unbalanced panels with large N and T, and reta...
Pesaran-Timmermann Test
Introduced by Pesaran and Timmermann (1992), the PT test is a nonparametric procedure that evaluates whether a forecasting model correctly predicts the direction (sign) of a target variable more often than would be expected by chance. It is...
Pharmacokinetic Compartment Model
The pharmacokinetic compartment model represents the body as one or more hypothetical compartments interconnected by first-order rate processes, describing how a drug is absorbed, distributed, and eliminated over time. Systematized by Gibal...
Philadelphia Geriatric Center Morale Scale
The Philadelphia Geriatric Center Morale Scale (PGCMS) is a classic self-report instrument for measuring morale — a broad sense of psychological well-being — in older adults. Developed by M. Powell Lawton and presented in revised 17-item fo...
Phillips-Ouliaris Test
The Phillips-Ouliaris test, introduced by Phillips and Ouliaris in their 1990 Econometrica article, is a residual-based nonparametric procedure for testing the null hypothesis of no cointegration among a set of integrated I(1) time series....
Phillips-Perron Test
The Phillips-Perron test, proposed by Peter Phillips and Pierre Perron in 1988, tests for a unit root in a time series, like the Augmented Dickey-Fuller test, but corrects for autocorrelation and heteroskedasticity in the errors non-paramet...
Phillips-Perron unit root test
The Phillips-Perron (PP) test is a nonparametric unit root test for time series that corrects for serial correlation and heteroscedasticity in the error term without adding lagged differences. Introduced by Phillips and Perron (1988), it ap...
Place Attachment in Recreation Settings
Place attachment in recreation settings is the emotional and functional bond people form with the specific outdoor places where they recreate. Following Williams and Roggenbuck's 1989 conceptualization and Williams and Vaske's influential 2...
Place-to-Place Migration Model
The place-to-place migration model explains and predicts the gross number of people moving from each origin region to each destination region as a function of conditions at both ends and the distance between them. It descends from the gravi...
Placebo Test in Education Research
A placebo test is a falsification check used in quasi-experimental education research to validate a causal design. By applying the same estimator to a time period, group, or outcome where no real effect should exist, researchers verify that...
Placebo Tests
Placebo tests are a family of falsification checks that probe the credibility of a causal claim by re-running the analysis on a fake treatment, a false intervention date, or an outcome that should not have been affected. The approach was po...
Plackett-Burman Design
The Plackett-Burman design is a two-level orthogonal screening design introduced by R.L. Plackett and J.P. Burman in 1946 that allows researchers to estimate the main effect of each factor independently using the smallest possible number of...
Plackett-Luce Model
The Plackett-Luce model is a probabilistic framework for analysing and predicting rank-ordered data. Introduced by Robin Plackett (1975) — building on R. Duncan Luce's earlier axiom of choice (1959) — it models the probability of any comple...
Pluralistic Walkthrough
The Pluralistic Walkthrough is a usability inspection method that brings together users, developers, and usability specialists to walk through an interface and voice their reactions and concerns. Developed by Randolph Bias in 1992, this met...