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The analysis of zero‐inflated count data: Beyond zero‐inflated Poisson regression.
British Journal of Mathematical and Statistical Psychology, 2011Infrequent count data in psychological research are commonly modelled using zero‐inflated Poisson regression. This model can be viewed as a latent mixture of an “always‐zero” component and a Poisson component. Hurdle models are an alternative class of two‐component models that are seldom used in psychological research, but clearly separate the zero ...
Loeys, Tom +3 more
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Attribute Charts for Zero-Inflated Processes
Communications in Statistics - Simulation and Computation, 2008The classical Shewhart c-chart and p-chart which are constructed based on the Poisson and binomial distributions are inappropriate in monitoring zero-inflated counts. They tend to underestimate the dispersion of zero-inflated counts and subsequently lead to higher false alarm rate in detecting out-of-control signals. Another drawback of these charts is
C. H. Sim, M. H. Lim
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Smooth Tests for the Zero‐Inflated Poisson Distribution
Biometrics, 2005Summary In this article we construct three smooth goodness‐of‐fit tests for testing for the zero‐inflated Poisson (ZIP) distribution against general smooth alternatives in the sense of Neyman. We apply our tests to a data set previously claimed to be ZIP distributed, and show that the ZIP is not a good model to describe the data.
Rayner, J. C. W, Thas, Olivier
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Journal of Biopharmaceutical Statistics, 2020
In longitudinal studies measurements are often collected on different types of responses for each individual. These may contain several longitudinally measured responses (such as the CD4 count) and the time at which an event occurs (e.g., HIV, death, or dropout from the study). These outcomes are often separately analyzed. Compared to separate modeling,
Mojtaba, Zeinali Najafabadi +2 more
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In longitudinal studies measurements are often collected on different types of responses for each individual. These may contain several longitudinally measured responses (such as the CD4 count) and the time at which an event occurs (e.g., HIV, death, or dropout from the study). These outcomes are often separately analyzed. Compared to separate modeling,
Mojtaba, Zeinali Najafabadi +2 more
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On the Costs of Zero Inflation
Économie appliquée, 1995The costs of inflation under the demand curve for money are vanishingly small since one deals only with currency, itself endogenous, because in Canada and other leading countries, non-interest bearing cash reserves as part of fiat money no longer exist.
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Semiparametric Analysis of Zero‐Inflated Count Data
Biometrics, 2006SummaryMedical and public health research often involve the analysis of count data that exhibit a substantially large proportion of zeros, such as the number of heart attacks and the number of days of missed primary activities in a given period. A zero‐inflated Poisson regression model, which hypothesizes a two‐point heterogeneity in the population ...
Lam, KF, Bun Cheung, Y, Xue, H
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The case for zero inflation [PDF]
, 1988 An argument that a monetary policy aimed at eliminating long-run inflation would benefit society by removing price distortion, increasing economic growth, adding liquidity to the economy, and reducing uncertainty associated with price-level drift.
William T. Gavin, Alan C. Stockman
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Biometrics, 2001
Summary. Count data often show a higher incidence of zero counts than would be expected if the data were Poisson distributed. Zero‐inflated Poisson regression models are a useful class of models for such data, but parameter estimates may be seriously biased if the nonzero counts are overdispersed in relation to the Poisson distribution.
Ridout, Martin +2 more
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Summary. Count data often show a higher incidence of zero counts than would be expected if the data were Poisson distributed. Zero‐inflated Poisson regression models are a useful class of models for such data, but parameter estimates may be seriously biased if the nonzero counts are overdispersed in relation to the Poisson distribution.
Ridout, Martin +2 more
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A Score Test for Zero Inflation in a Poisson Distribution
Biometrics, 1995When analyzing Poisson-count data sometimes a lot of zeros are observed. When there are too many zeros a zero-inflated Poisson distribution can be used. A score test is presented to test whether the number of zeros is too large for a Poisson distribution to fit the data well.
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Small Area Estimation for Zero-Inflated Data
Communications in Statistics - Simulation and Computation, 2011The commonly used method of small area estimation (SAE) under a linear mixed model may not be efficient if data contain substantial proportion of zeros than would be expected under standard model assumptions (hereafter zero-inflated data). The authors discuss the SAE for zero-inflated data under a two-part random effects model that account for excess ...
Hukum Chandra, U. C. Sud
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