Statistics — Page 75
Explore statistical methods, their assumptions, interpretation and limitations.
Research field
Method family
Wordscores
Wordscores is a text-based scaling method developed by Laver, Benoit, and Garry (2003) that estimates the policy positions of political actors based on word frequencies in their texts. By comparing word usage in reference texts of known pos...
Workaholism Scale
Workaholism scales measure the addiction-like compulsion to work — the tendency to work excessively hard combined with an inner, hard-to-resist drive to keep working. Janet Spence and Ann Robbins introduced the first systematic measure, the...
Wright Map Analysis
A Wright map (item-person map) is the signature graphical output of Rasch measurement: it places persons and items on the same vertical scale, with examinee abilities on one side and item difficulties on the other, both in logits. Because a...
Zarit Burden Interview
The Zarit Burden Interview (ZBI) is the most widely used self-report measure of caregiver burden — the physical, emotional, social, and financial strain experienced by people who care for an impaired older relative, most often someone with...
Zero-Inflated Negative Binomial Regression
Zero-Inflated Negative Binomial regression is a count model, introduced by Greene (1994), that handles count data showing both an excess of zeros and overdispersion. It combines a binary inflation process that generates structural zeros wit...
Zero-Inflated Poisson Regression
Zero-Inflated Poisson regression is a two-component model for count data that contains more zeros than an ordinary Poisson model can explain. Introduced by Diane Lambert in 1992, it combines a logistic model for the zero-generating mechanis...
Zero-inflated model
A zero-inflated model is a two-component mixture regression designed for count outcomes that contain more zero values than a standard Poisson or negative binomial distribution can accommodate. One component is a binary process that generate...
Zivot-Andrews Structural Break Test
The Zivot-Andrews (ZA) test is a unit root test that endogenously identifies the most likely location of a single structural break in a time series. Unlike the standard ADF test, it does not require the researcher to pre-specify when the br...
Zivot-Andrews Test
The Zivot-Andrews (ZA) test, introduced by Eric Zivot and Donald Andrews in 1992, is a sequential unit-root test that allows for a single structural break at an unknown date. It extends the augmented Dickey-Fuller framework by endogenously...